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HAL Id: tel-00712153 https://tel.archives-ouvertes.fr/tel-00712153 Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés. Analyzing individual-based models of microbial systems Nabil Mabrouk To cite this version: Nabil Mabrouk. Analyzing individual-based models of microbial systems. Bio-Informatique, Biolo- gie Systémique [q-bio.QM]. Université Blaise Pascal - Clermont-Ferrand II, 2010. Français. NNT: 2010CLF22008. tel-00712153

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Page 1: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

HAL Id: tel-00712153https://tel.archives-ouvertes.fr/tel-00712153

Submitted on 26 Jun 2012

HAL is a multi-disciplinary open accessarchive for the deposit and dissemination of sci-entific research documents, whether they are pub-lished or not. The documents may come fromteaching and research institutions in France orabroad, or from public or private research centers.

L’archive ouverte pluridisciplinaire HAL, estdestinée au dépôt et à la diffusion de documentsscientifiques de niveau recherche, publiés ou non,émanant des établissements d’enseignement et derecherche français ou étrangers, des laboratoirespublics ou privés.

Analyzing individual-based models of microbial systemsNabil Mabrouk

To cite this version:Nabil Mabrouk. Analyzing individual-based models of microbial systems. Bio-Informatique, Biolo-gie Systémique [q-bio.QM]. Université Blaise Pascal - Clermont-Ferrand II, 2010. Français. �NNT :2010CLF22008�. �tel-00712153�

Page 2: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

◆ ❞✬♦r❞r❡✿ ❉✳❯✿ ✷✵✵✽ ❊❉❙P■❈✿ ✹✼✹

❯♥✐✈❡rs✐té ❇❧❛✐s❡ P❛s❝❛❧ ✲ ❈❧❡r♠♦♥t ■■

➱❝♦❧❡ ❉♦❝t♦r❛❧❡

❙❝✐❡♥❝❡s P♦✉r ❧✬■♥❣é♥✐❡✉r ❉❡ ❈❧❡r♠♦♥t✲❋❡rr❛♥❞

❚❤ès❡

Prés❡♥té❡ ♣❛r

◆❛❜✐❧ ▼❆❇❘❖❯❑

■♥❣é♥✐❡✉r ❡♥ ■♥❞✉str✐❡s ❆❧✐♠❡♥t❛✐r❡s

❉❊❆ ❡♥ ▼♦❞é❧✐s❛t✐♦♥ ❡♥ ❍②❞r❛✉❧✐q✉❡ ❡t ❊♥✈✐r♦♥♥❡♠❡♥t

♣♦✉r ♦❜t❡♥✐r ❧❡ ❣r❛❞❡ ❞❡

❉♦❝t❡✉r ❞✬❯♥✐✈❡rs✐té

❙♣é❝✐❛❧✐té✿ ■♥❢♦r♠❛t✐q✉❡

❆♥❛❧②③✐♥❣ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞♠♦❞❡❧s ♦❢ ♠✐❝r♦❜✐❛❧ s②st❡♠s

❙♦✉t❡♥✉❡ ♣✉❜❧✐q✉❡♠❡♥t ❧❡ ✼ ❥❛♥✈✐❡r ✷✵✶✵ ❞❡✈❛♥t ❧❡ ❥✉r②✿

Prés✐❞❡♥t ✿ ❉❛✈✐❞ ❍✐❧❧

Pr♦❢❡ss❡✉r✱ ❯♥✐✈❡rs✐té ❇❧❛✐s❡ P❛s❝❛❧✱ ❈❧❡r♠♦♥t✲❋❡rr❛♥❞

❘❛♣♣♦rt❡✉r ✿ ❈r✐st✐❛♥ P✐❝✐♦r❡❛♥✉

Pr♦❢❡ss❡✉r ❛ss♦❝✐é✱ ❯♥✐✈❡rs✐té ❚❡❝❤♥✐q✉❡ ❞❡ ❉❡❧❢t✱ P❛②s✲❇❛s

❏❡❛♥✲❉❛♥✐❡❧ ❩✉❝❦❡r

❉✐r❡❝t❡✉r ❞❡ ❘❡❝❤❡r❝❤❡✱ ■❘❉✱ P❛r✐s

❊①❛♠✐♥❛t❡✉r ✿ ❚❤é♦❞♦r❡ ❇♦✉❝❤❡③

❈❤❛r❣é ❞❡ ❘❡❝❤❡r❝❤❡✱ ❈❡♠❛❣r❡❢✱ ❆♥t♦♥②

❉✐r❡❝t❡✉rs ❞❡ t❤ès❡ ✿ ●✉✐❧❧❛✉♠❡ ❉❡❢❢✉❛♥t

❉✐r❡❝t❡✉r ❞❡ r❡❝❤❡r❝❤❡✱ ❈❡♠❛❣r❡❢✱ ❈❧❡r♠♦♥t✲❋❡rr❛♥❞

❈❧❛✉❞❡ ▲♦❜r②

Pr♦❢❡ss❡✉r✱ ❯♥✐✈❡rs✐té ❞❡ ◆✐❝❡

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❆❝❦♥♦✇❧❡❞❣♠❡♥t

■ ✇♦✉❧❞ ❧✐❦❡ t♦ ❡①♣r❡ss ♠② ❣r❛t✐t✉❞❡ t♦ ❛❧❧ ✇❤♦ ❤❛✈❡ ❝♦♥tr✐❜✉t❡❞ t♦ t❤❡ ❝♦♠♣❧❡t✐♦♥

♦❢ t❤✐s t❤❡s✐s ✐♥ ♦♥❡ ✇❛② ♦r ❛♥♦t❤❡r✳

❙♣❡❝✐❛❧ t❤❛♥❦s ❣♦ t♦

• ❉r✳ ●✉✐❧❧❛✉♠❡ ❉❡✛✉❛♥t ❛♥❞ Pr♦❢✳ ❈❧❛✉❞❡ ▲♦❜r② ❢♦r s✉♣♣♦rt✐♥❣ ♠❡ ✐♥ t❤❡ ❧❛st

②❡❛rs ❛♥❞ ❢♦r t❤❡✐r ❣✉✐❞❛♥❝❡ ❞✉r✐♥❣ ♠② ❞✐ss❡rt❛t✐♦♥✳

• Pr♦❢✳ ❉❛✈✐❞ ❍✐❧❧✱ ❉r✳ ❈r✐st✐❛♥ P✐❝✐♦r❡❛♥✉✱ ❉r✳ ❏❡❛♥✲❉❛♥✐❡❧ ❩✉❝❦❡r ❛♥❞ ❉r✳

❚❤❡♦❞♦r❡ ❇♦✉❝❤❡③ ✇❤♦ ❦✐♥❞❧② ❛❝❝❡♣t❡❞ t♦ r❡✈✐❡✇ ♠② ❞✐ss❡rt❛t✐♦♥✳

• ▼② ❝♦❧❧❡❛❣✉❡s ❛♥❞ ❢r✐❡♥❞s ✐♥t t❤❡ ▲❛❜♦r❛t♦r② ♦❢ ❊♥❣✐♥❡❡r✐♥❣ ❢♦r ❈♦♠♣❧❡①

❙②st❡♠s ❛♥❞ ✐♥ t❤❡ ▼❊❘❊ t❡❛♠ ❢♦r t❤❡✐r ❤❡❧♣ ❛♥❞ s✉♣♣♦rt✳

• ❆❧❧ t❤❡ ♣❛rt♥❡rs ♦❢ t❤❡ P❆❚❘❊❙ ❊❯ ♣r♦❥❡❝t ❢♦r t❤❡ ✐♥t❡r❡st✐♥❣ ❞✐s❝✉ss✐♦♥s ❛♥❞

t❤❡ ♥✐❝❡ ♠♦♠❡♥ts ■ s❤❛r❡❞ ✇✐t❤ t❤❡♠✳

• ▼② ❢❛♠✐❧② ❛♥❞ ❢r✐❡♥❞s ❢♦r t❤❡✐r s✉♣♣♦rt ❞✉r✐♥❣ ❛❧❧ t❤❡s❡ ②❡❛rs✳

• ▼② ❧♦✈❡❧② ❝❤✐❧❞r❡♥s✱ ❆♥❛✐s✱ ❆❞❛♠ ❛♥❞ ▲é❛ t♦ ✇❤♦♠❡ ■ ❞❡❞✐❝❛t❡ t❤✐s t❤❡s✐s✳

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❆❜str❛❝t

❚❤❡r❡ ✐s ❛ ❞❡❜❛t❡ ✐♥ ❡❝♦❧♦❣② ❜❡t✇❡❡♥ t❤♦s❡ ❢❛✈♦r✐♥❣ s✐♠♣❧❡ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡✲

♠❛t✐❝❛❧ ♠♦❞❡❧s ❝♦♥t❛✐♥✐♥❣ ♦♥❧② ❛ ❢❡✇ ❡q✉❛t✐♦♥s ❡①♣r❡ss✐♥❣ ❛ s♠❛❧❧ ♥✉♠❜❡r ♦❢ ❣❡♥✲

❡r❛❧ ♣r✐♥❝✐♣❧❡s ❛♥❞ t❤♦s❡ ♣r❡❢❡rr✐♥❣ ❝♦♠♣❧❡① ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧s t❤❛t ❛r❡ ♠♦r❡

str✉❝t✉r❛❧❧② r❡❛❧✐st✐❝ ✇✐t❤ ❛ ♠♦r❡ ❞❡t❛✐❧❡❞ r❡♣r❡s❡♥t❛t✐♦♥ ♦❢ t❤❡ ❜❛s✐❝ ♣r♦❝❡ss❡s ❛♥❞

✐♥t❡r❛❝t✐♦♥s ❛t t❤❡ ❧❡✈❡❧ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ■♥ t❤✐s t❤❡s✐s ✇❡ ❛tt❡♠♣t t♦ ❜r✐❞❣❡ t❤❡s❡

t✇♦ ❛♣♣r♦❛❝❤❡s ❜② ❞❡r✐✈✐♥❣ ❞❡t❡r♠✐♥✐st✐❝ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧s ♦❢ ♠✐❝r♦✲

❜✐❛❧ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧s✳ ❲❡ ✐❧❧✉str❛t❡ t❤❡ ❛♣♣r♦❛❝❤ ♦♥ t❤❡ ❡①❛♠♣❧❡ ♦❢ ❜✐♦✜❧♠

❣r♦✇t❤ ✇✐t❤ ✐♠♠♦t✐❧❡ ❛♥❞ ♠♦t✐❧❡ ❜❛❝t❡r✐❛✳ ❲❡ s❤♦✇ t❤❛t ♠♦♠❡♥t ♠♦❞❡❧ ❝❛♥ ❝❛♣t✉r❡

t❤❡ ♠❛✐♥ ❢❡❛t✉r❡s ♦❢ s♣❛t✐❛❧ ♣❛tt❡r♥ t❤❛t ❛r✐s❡ ✐♥ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧s✳ ❋✐♥❛❧❧② ✇❡ ❛ss❡ss t❤❡ ❧✐♠✐t❛t✐♦♥ ♦❢ ♠♦♠❡♥t ♠♦❞❡❧s ✐♥ ❝❛♣t✉r✐♥❣ t❤❡ ❡✛❡❝t

♦❢ t❤❡ ❧♦❝❛❧ ✢✉❝t✉❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✬s ❡♥✈✐r♦♥♠❡♥t✳

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❘és✉♠é

❈❡tt❡ t❤ès❡ s✬✐♥s❝r✐t ❞❛♥s ❧❡ ❝❛❞r❡ ❞✉ ❞é❜❛t ❡♥ é❝♦❧♦❣✐❡ t❤é♦r✐q✉❡ ❡♥tr❡ ❝❡✉① q✉✐

❢❛✈♦r✐s❡♥t ❧❡s ♠♦❞è❧❡s ♠❛t❤é♠❛t✐q✉❡s ❛❣ré❣és ❝♦♥t❡♥❛♥t ✉♥ ♥♦♠❜r❡ r❡❧❛t✐✈❡♠❡♥t

❢❛✐❜❧❡ ❞✬éq✉❛t✐♦♥s ❡①♣r✐♠❛♥t q✉❡❧q✉❡s ♣r✐♥❝✐♣❡s ❣é♥ér❛✉① ❡t ❝❡✉① q✉✐ ♣ré❢èr❡♥t ❧❡s

♠♦❞è❧❡s ✐♥❞✐✈✐❞✉s✲❝❡♥tré ✭♠✉❧t✐✲❛❣❡♥ts✮ q✉✐ s♦♥t str✉❝t✉r❡❧❧❡♠❡♥t ♣❧✉s ré❛❧✐st❡s ❡t

❝♦♠♣r❡♥♥❡♥t ✉♥❡ r❡♣rés❡♥t❛t✐♦♥ ❞ét❛✐❧❧é❡s ❞❡s ♣r♦❝❡ss✉s ❡t ✐♥t❡r❛❝t✐♦♥s à ❧✬é❝❤❡❧❧❡

❞❡ ❧✬✐♥❞✐✈✐❞✉✳ ❉❛♥s ❝❡tt❡ t❤ès❡ ♥♦✉s ♣r♦♣♦s♦♥s ❞✬ét❛❜❧✐r ✉♥ ❧✐❡♥ ❡♥tr❡ ❝❡s ❞❡✉①

❛♣♣r♦❝❤❡s ❡♥ ❞ér✐✈❛♥t ❞❡s ♠♦❞è❧❡s ❞ét❡r♠✐♥✐st❡s ❜❛sés s✉r ❧❡s ♠♦♠❡♥ts s♣❛t✐❛✉①

❡t ❛♣♣r♦①✐♠❛♥t ❧❛ ❞②♥❛♠✐q✉❡ ❞❡s ♠♦❞è❧❡s ✐♥❞✐✈✐❞✉s✲❝❡♥trés ❞❡ s②stè♠❡s ♠✐❝r♦❜✐✲

❡♥s✳ ◆♦✉s ✐❧❧✉str♦♥s ❝❡tt❡ ❛♣♣r♦❝❤❡ s✉r ❧✬❡①❡♠♣❧❡ ❞❡ ❝r♦✐ss❛♥❝❡ ❞✬✉♥ ❜✐♦✜❧♠ ❢♦r♠é

♣❛r ❞❡s ❜❛❝tér✐❡s ♠♦❜✐❧❡s ♦✉ ✐♠♠♦❜✐❧❡s✳ ◆♦✉s ♠♦♥tr♦♥s q✉❡ ❧❡s ♠♦❞è❧❡s ❞❡s ♠♦✲

♠❡♥ts ♣❡✉✈❡♥t r❡♥❞r❡ ❝♦♠♣t❡ ❞❡s ♣r✐♥❝✐♣❛❧❡s ♣r♦♣r✐étés ❞❡s str✉❝t✉r❡s s♣❛t✐❛❧❡s

♦❜t❡♥✉❡s ♣❛r s✐♠✉❧❛t✐♦♥ ✐♥❞✐✈✐❞✉s✲❝❡♥tré❡✳ ❊♥✜♥ ♥♦✉s ❡①♣❧♦r♦♥s ❧❡s ❧✐♠✐t❡s ❞❡s

♠♦❞è❧❡s ❞❡s ♠♦♠❡♥ts ♥♦t❛♠♠❡♥t à r❡♥❞r❡ ❝♦♠♣t❡ ❞❡ ❧✬❡✛❡t ❞❡s ✢✉❝t✉❛t✐♦♥s ❧♦❝❛❧❡s

❞❡ ❧✬❡♥✈✐r♦♥♥❡♠❡♥t ❞❡s ✐♥❞✐✈✐❞✉s ❧♦rsq✉❡ ❝❡❧❧❡s ❝✐ ❛✛❡❝t❡♥t ❧❛ ❞②♥❛♠✐q✉❡ ❞✉ s②stè♠❡

♠✐❝r♦❜✐❡♥ s✐♠✉❧é ♣❛r ❧❡ ♠♦❞è❧❡ ✐♥❞✐✈✐❞✉s✲❝❡♥tré✳

Page 9: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and
Page 10: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❈♦♥t❡♥ts

✶ ■♥tr♦❞✉❝t✐♦♥ ✶

✶✳✶ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♣❡rs♣❡❝t✐✈❡ ♦❢ ♠✐❝r♦❜✐❛❧ s②st❡♠s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶

✶✳✷ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✐♥❣ ♦❢ ♠✐❝r♦❜✐❛❧ s②st❡♠s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷

✶✳✸ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧✐♥❣ ♦❢ ♠✐❝r♦❜✐❛❧ ❡❝♦s②st❡♠s ✳ ✳ ✳ ✳ ✳ ✸

✶✳✹ ❉❡❜❛t❡ ❜❡t✇❡❡♥ ■❇▼ ❛♥❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹

✶✳✺ ❚❤❡s✐s s❝♦♣❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺

✶✳✺✳✶ ❆♣♣r♦①✐♠❛t✐♥❣ s♣❛t✐❛❧❧② ❡①♣❧✐❝✐t ■❇▼s ✇✐t❤ ♠♦♠❡♥t ♠❡t❤♦❞s ✻

✶✳✻ ▼❡t❤♦❞s ❛♥❞ t♦♦❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼

✶✳✻✳✶ ■❇▼ ❞❡s❝r✐♣t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼

✶✳✻✳✷ ■❇▼ ✐♠♣❧❡♠❡♥t❛t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼

✶✳✻✳✸ ❊①♣❧♦r✐♥❣ t❤❡ ■❇▼s ✉s✐♥❣ ❙✐♠❊①♣❧♦r❡r ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽

✶✳✼ ❘❡♣♦rt ♦✉t❧✐♥❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽

✷ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ✶✶

✷✳✶ ▼♦❞❡❧✐♥❣ ♠✐❝r♦❜✐❛❧ s♣❛t✐❛❧ ♣❛tt❡r♥s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✷

✷✳✷ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸

✷✳✸ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✹

✷✳✸✳✶ ❖✈❡r✈✐❡✇ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✹

✷✳✸✳✷ ❉❡s✐❣♥ ❈♦♥❝❡♣ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✺

✷✳✸✳✸ ❉❡t❛✐❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✺

✷✳✸✳✹ ▼♦❞❡❧ ♣❛r❛♠❡t❡rs ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼

✷✳✹ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ s✐♠✉❧❛t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼

✷✳✺ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽

✷✳✻ ❈♦♠♣❛r✐♥❣ t❤❡ ■❇▼ ✇✐t❤ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✷

✷✳✼ ❉✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✸

✸ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥② ❣r♦✇t❤ ✷✾

✸✳✶ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵

✸✳✶✳✶ ❖✈❡r✈✐❡✇ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵

✸✳✶✳✷ ❉❡s✐❣♥ ❝♦♥❝❡♣ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✶

✸✳✶✳✸ ❉❡t❛✐❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✷

✸✳✶✳✹ P❛r❛♠❡t❡rs ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✷

✸✳✶✳✺ ▼♦❞❡❧ ♦✉t♣✉ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✸

✸✳✶✳✻ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✇✐t❤ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ ✳ ✳ ✳ ✸✸

✸✳✶✳✼ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✹

✸✳✶✳✽ ❙♦❧✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✸

✸✳✷ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✇✐t❤ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✹✺

✸✳✷✳✶ ❉❡♥s✐t② ✐♥❞❡♣❡♥❞❡♥t ❣r♦✇t❤ ♠♦❞❡❧ ✭b′1 = 0✮ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✺

✸✳✷✳✷ ❉❡♥s✐t② ❞❡♣❡♥❞❛♥t ❞✐✈✐s✐♦♥ ♠♦❞❡❧ ✭b′1 > 0✮ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✽

Page 11: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✈✐✐✐ ❈♦♥t❡♥ts

✸✳✸ ❉✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✾

✸✳✹ ❆♥♥❡①❡ ❆✿ ❡①♣r❡ss✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✐♥ r❛❞✐❛❧ ❝♦♦r❞✐♥❛t❡s ✳ ✳ ✳ ✳ ✺✷

✹ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤ ❞❡t❛❝❤✲

♠❡♥t ✺✸

✹✳✶ ■♥tr♦❞✉❝t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✸

✹✳✷ ❆ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤ ❞❡t❛❝❤♠❡♥t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✹

✹✳✷✳✶ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✻

✹✳✸ ■❇▼ s✐♠✉❧❛t✐♦♥ r❡s✉❧ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✻

✹✳✹ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✼

✹✳✺ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ t❤❡ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✶

✹✳✻ ❉✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✷

✺ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡

❜❛❝t❡r✐❛ ✻✼

✺✳✶ ❇❛❝❦❣r♦✉♥❞ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✽

✺✳✷ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✾

✺✳✷✳✶ P✉r♣♦s❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵

✺✳✷✳✷ ❙t❛t❡ ✈❛r✐❛❜❧❡s ❛♥❞ s❝❛❧❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵

✺✳✷✳✸ ❙❝❛❧❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵

✺✳✷✳✹ Pr♦❝❡ss ♦✈❡r✈✐❡✇ ❛♥❞ s❝❤❡❞✉❧✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵

✺✳✷✳✺ ❉❡s✐❣♥ ❈♦♥❝❡♣ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✷

✺✳✷✳✻ ❙✉❜♠♦❞❡❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✷

✺✳✸ ❘❡s✉❧ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✼

✺✳✹ ❉✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✾

✻ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼ ✽✼

✻✳✶ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✽

✻✳✶✳✶ ❖✈❡r✈✐❡✇ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✽

✻✳✶✳✷ ❉❡t❛✐❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✵

✻✳✷ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✷

✻✳✷✳✶ ❋✐rst ♠♦♠❡♥t ❞②♥❛♠✐❝s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✷

✻✳✷✳✷ ❙❡❝♦♥❞ ♠♦♠❡♥t ❞②♥❛♠✐❝s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✸

✻✳✷✳✸ ❈❧♦s✉r❡ ♦❢ t❤❡ ♠♦♠❡♥t ❤✐❡r❛r❝❤② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✵

✻✳✷✳✹ ❙♦❧✈✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✵

✻✳✸ ❘❡s✉❧ts ❛♥❞ ❞✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✵

✻✳✹ ❈♦♥❝❧✉s✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✶

✼ ❊①♣❧♦r✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s ✐♥ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢ ❛ ♠✐✲

❝r♦❜✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✶✶✼

✼✳✶ ❙✐♠♣❧✐✜❡❞ ■❇▼ ❢♦r ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧❡ ❜❛❝✲

t❡r✐❛ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✼

✼✳✷ ◆✉♠❡r✐❝❛❧ ❡①♣❧♦r❛t✐♦♥ ♦❢ t❤❡ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✾

✼✳✸ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✷✵

Page 12: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❈♦♥t❡♥ts ✐①

✼✳✹ ❉✐s❝✉ss✐♦♥ ❛♥❞ ❝♦♥❝❧✉s✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✷✾

✽ ❈♦♥❝❧✉s✐♦♥ ✶✸✶

✽✳✶ P❡rs♣❡❝t✐✈❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸✸

❇✐❜❧✐♦❣r❛♣❤② ✶✸✺

Page 13: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and
Page 14: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❈❤❛♣t❡r ✶

■♥tr♦❞✉❝t✐♦♥

■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧s ✭■❇▼s✮ ❛♥❞ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ✭❆▼▼s✮

r❡♣r❡s❡♥t t✇♦ ❞✐✛❡r❡♥t ❛♣♣r♦❛❝❤❡s ❢♦r ♠♦❞❡❧✐♥❣ ❡❝♦❧♦❣✐❝❛❧ s②st❡♠s✳ ❚❤❡r❡ ✐s ❛ ❞❡❜❛t❡

✐♥ ❡❝♦❧♦❣② ❜❡t✇❡❡♥ t❤♦s❡ ❢❛✈♦r✐♥❣ s✐♠♣❧❡ ❆▼▼s ❝♦♥t❛✐♥✐♥❣ ♦♥❧② ❛ ❢❡✇ ❡q✉❛t✐♦♥s

❡①♣r❡ss✐♥❣ ❛ s♠❛❧❧ ♥✉♠❜❡r ♦❢ ❣❡♥❡r❛❧ ♣r✐♥❝✐♣❧❡s ❛♥❞ t❤♦s❡ ♣r❡❢❡rr✐♥❣ ❝♦♠♣❧❡① ■❇▼s

t❤❛t ❛r❡ ♠♦r❡ ✑str✉❝t✉r❛❧❧② r❡❛❧✐st✐❝✑ ✇✐t❤ ❛ ♠♦r❡ ❞❡t❛✐❧❡❞ r❡♣r❡s❡♥t❛t✐♦♥ ♦❢ t❤❡ ❜❛s✐❝

♣r♦❝❡ss❡s ❛♥❞ ✐♥t❡r❛❝t✐♦♥s ❛t t❤❡ ❧❡✈❡❧ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❬❆✉♠❛♥♥ ✷✵✵✼❪✳ ■♥ t❤✐s

t❤❡s✐s ✇❡ ❛❞♦♣t ❛ ❞♦✉❜❧❡✲♠♦❞❡❧✐♥❣ str❛t❡❣② ❬▲♦❜r② ✷✵✵✸❪ ❬❉❡✛✉❛♥t ✷✵✵✹❪ ❜② ✉s✐♥❣

✭s✐♠♣❧❡✮ ❆▼▼s t♦ ❝❤❡❝❦✱ ❛♥❛❧②③❡ ❛♥❞ ❛♣♣r♦①✐♠❛t❡ t❤❡ ❝♦♠♣❧❡① ❞②♥❛♠✐❝ ♦❢ ■❇▼s

♦❢ ♠✐❝r♦❜✐❛❧ s②st❡♠s✳

✶✳✶ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♣❡rs♣❡❝t✐✈❡ ♦❢ ♠✐❝r♦❜✐❛❧ s②st❡♠s

❚❤❡r❡ ✐s ❛♥ ✐♥❝r❡❛s✐♥❣ ❛✇❛r❡♥❡ss ✐♥ ♥❛t✉r❛❧ ❛♥❞ s♦❝✐❛❧ s❝✐❡♥❝❡s t❤❛t ❡❝♦❧♦❣✐❝❛❧ ❛s

✇❡❧❧ ❛s s♦❝✐♦✲❡❝♦♥♦♠✐❝ s②st❡♠s s❤❛r❡ ❝♦♠♠♦♥ ❝❤❛r❛❝t❡r✐st✐❝s ♦❢ ❝♦♠♣❧❡① s②st❡♠s

❜✉✐❧t ♦❢ ✐♥t❡r❛❝t✐♥❣ ✐♥❞✐✈✐❞✉❛❧ ❛❣❡♥ts ❬▲❡✈✐♥ ✶✾✾✽❪ ❬❆rt❤✉r ✶✾✾✼❪ ❬❉❡✛✉❛♥t ✷✵✵✺❪

❬❘❛♠♠❡❧ ✷✵✵✼❪✳ ❆ ♠❛❥♦r ❝❤❛❧❧❡♥❣❡ ✐♥ t❤❡ st✉❞② ♦❢ t❤❡s❡ ❝♦♠♣❧❡① s②st❡♠s ✐s t♦

✉♥❞❡rst❛♥❞ ❤♦✇ s❡❡♠✐♥❣❧② ♦r❣❛♥✐③❡❞ ❝♦❧❧❡❝t✐✈❡ ❜❡❤❛✈✐♦r ❡♠❡r❣❡s ♦✉t ♦❢ t❤❡ s♠❛❧❧✲

s❝❛❧❡ ✐♥t❡r❛❝t✐♦♥s ❜❡t✇❡❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❈♦♠♣❧❡① s②st❡♠ r❡s❡❛r❝❤ t❡♥❞s t♦ ❛❞♦♣t

❛ ❜♦tt♦♠✲✉♣ ❛♣♣r♦❛❝❤✱ ❞❡s❝r✐❜✐♥❣ ❦✐♥❞s ♦❢ ❛❣❡♥ts ❛♥❞ ❡♥✈✐r♦♥♠❡♥ts ❛♥❞ t❤❡♥ ❡①♣❡r✲

✐♠❡♥t❛❧❧② ✜♥❞✐♥❣ ♦✉t ✇❤❛t ❦✐♥❞ ♦❢ ❝♦♠♣❧❡① ❞②♥❛♠✐❝s ❛r❡ ❡①❤✐❜✐t❡❞ ❜② t❤❡ s②st❡♠

❛❣❡♥ts ❬❘❛✐❧s❜❛❝❦ ✷✵✵✶❪✳ ❇♦tt♦♠✲✉♣ ♠♦❞❡❧s t❤❛t r❡♣r❡s❡♥t t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ t❤❡✐r

✐♥t❡r❛❝t✐♦♥s ❡①♣❧✐❝✐t❧② ❛r❡ ❜r♦❛❞❧② ❝❛❧❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧s ✭■❇▼s✮✳

▼✐❝r♦❜✐❛❧ ❡❝♦s②st❡♠s ❡①❤✐❜✐t ♠❛♥② ❢❡❛t✉r❡s ♦❢ s✉❝❤ ❝♦♠♣❧❡① s②st❡♠s

❬❈r❛✇❢♦r❞ ✷✵✵✺❪✳ ❚❤❡② ❛r❡ ❜❛s✐❝❛❧❧② ❢♦r♠❡❞ ✇✐t❤ ✐♥❞✐✈✐❞✉❛❧ ♠✐❝r♦❜✐❛❧ ❝❡❧❧s t❤❛t ❡♥✲

❝❛♣s✉❧❛t❡ ❛❝t✐♦♥✱ ✐♥❢♦r♠❛t✐♦♥ st♦r❛❣❡ ❛♥❞ ♣r♦❝❡ss✐♥❣ ❬❑r❡❢t ✶✾✾✽❪✳ ❇❡❝❛✉s❡ ♦❢ t❤❡✐r

s♠❛❧❧ s✐③❡ ❝♦♠♣❛r❡❞ t♦ t❤❡ s✐③❡ ♦❢ t❤❡✐r ❡♥✈✐r♦♥♠❡♥t✱ ♠✐❝r♦❜✐❛❧ ❝❡❧❧s ❤❛✈❡ ❛ ❧♦❝❛❧ ♣❡r✲

❝❡♣t✐♦♥ ♦❢ t❤❡✐r ✇♦r❧❞✳ ❚❤❡② r❡❛❝t ❛♥❞ ❛❞❛♣t ♦♥❧② t♦ t❤❡✐r ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t✳ ❚❤❡

❝♦❧❧❡❝t✐✈❡ ❜❡❤❛✈✐♦r t❤❛t r❡s✉❧ts ❢r♦♠ t❤❡s❡ ❧♦❝❛❧ ✐♥t❡r❛❝t✐♦♥s ♠❛②✱ ❤♦✇❡✈❡r✱ ❡①❤✐❜✐t

s❡✈❡r❛❧ ♠❛❝r♦s❝❛❧❡ r❡❣✉❧❛r✐t✐❡s ❛♥❞ ❡♠❡r❣❡♥t ♣r♦♣❡rt✐❡s✳

❆ ▼✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ✐s ♦♥❡ ♦❢ t❤❡ ♠♦st r❡♠❛r❦❛❜❧❡ ❡①❛♠♣❧❡s ♦❢ s✉❝❤ ❛ s②st❡♠✳

❇✐♦✜❧♠s ❛r❡ t❤✐♥ s❧✐♠② ❧❛②❡rs ❢♦r♠❡❞ ❜② ❜❛❝t❡r✐❛ ❛♥❞ t❤❡✐r ❡①tr❛❝❡❧❧✉❧❛r ♣r♦❞✉❝ts

♦♥ ❤②❞r❛t❡❞ s✉r❢❛❝❡s✳ ❚❤❡② ❛r❡ ✉❜✐q✉✐t♦✉s ✐♥ ♥❛t✉r❡ ❛♥❞ r❡♣r❡s❡♥t t❤❡ ♣r❡❢❡r❡♥t✐❛❧

❣r♦✇t❤ ♠♦❞❡ ♦❢ ♠❛♥② ❜❛❝t❡r✐❛❧ s♣❡❝✐❡s✳ ❯s✐♥❣ ❛❞✈❛♥❝❡❞ ♠✐❝r♦s❝♦♣② ❛♥❞ ♠♦❧❡❝✉❧❛r

t❡❝❤♥♦❧♦❣✐❡s✱ r❡s❡❛r❝❤❡rs ❤❛✈❡ s❤♦✇♥ t❤❛t ❜✐♦✜❧♠s r❡♣r❡s❡♥t ❛ ❜✐♦❧♦❣✐❝❛❧ s②st❡♠ ✇✐t❤

Page 15: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✷ ❈❤❛♣t❡r ✶✳ ■♥tr♦❞✉❝t✐♦♥

❛ ❤✐❣❤ ❧❡✈❡❧ ♦❢ ♦r❣❛♥✐③❛t✐♦♥ ✇❤❡r❡ ❜❛❝t❡r✐❛ ❢♦r♠ str✉❝t✉r❡❞✱ ❝♦♦r❞✐♥❛t❡❞✱ ❢✉♥❝t✐♦♥❛❧

❝♦♠♠✉♥✐t✐❡s ❬❖✬❚♦♦❧❡ ✷✵✵✵❪✳ ❚❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡s❡ ♦r❣❛♥✐③❡❞ ✑❝✐t✐❡s ♦❢ ♠✐❝r♦❜❡s✑

✐s ❤♦✇❡✈❡r t♦ ❛ ❧❛r❣❡ ♣❛rt ♠❡❞✐❛t❡❞ ❜② ❧♦❝❛❧ ✐♥t❡r❛❝t✐♦♥s ❜❡t✇❡❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧

❝❡❧❧s ❛♥❞ ✇✐t❤ t❤❡✐r ✐♠♠❡❞✐❛t❡ s✉rr♦✉♥❞✐♥❣ ❡♥✈✐r♦♥♠❡♥t✳ ❇② ✈✐❡✇✐♥❣ s✉❝❤ s②st❡♠s

❛s ❝♦♠♣❧❡① s②st❡♠s ❢♦r♠❡❞ ✇✐t❤ ❧♦❝❛❧❧② ✐♥t❡r❛❝t✐♥❣ ✐♥❞✐✈✐❞✉❛❧s✱ ♠✐❝r♦❜✐❛❧ ❡❝♦❧♦❣②

❝❛♥ t❛❦❡ ❜❡♥❡✜t ❢r♦♠ t♦♦❧s ❛♥❞ ❛♣♣r♦❛❝❤❡s ✭❧✐❦❡ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✐♥❣ ❛♣✲

♣r♦❛❝❤✮ ❞❡✈❡❧♦♣❡❞ t♦ st✉❞② ❝♦♠♣❛r❛❜❧❡ s②st❡♠s ✐♥ ♦t❤❡r ✜❡❧❞s ♦❢ s❝✐❡♥❝❡✳

✶✳✷ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✐♥❣ ♦❢ ♠✐❝r♦❜✐❛❧ s②st❡♠s

❚❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✐♥❣ ❛♣♣r♦❛❝❤ ❛tt❡♠♣ts t♦ ❝❛♣t✉r❡ t❤❡ ♣r♦♣❡rt✐❡s ❛♥❞

❞②♥❛♠✐❝ ♦❢ ❛ ♣♦♣✉❧❛t✐♦♥ ❜② ❞❡s❝r✐❜✐♥❣ ❛❧❧ t❤❡ ❛❝t✐♦♥s ♦❢ ✐ts ❝♦♥st✐t✉t✐✈❡ ✐♥❞✐✈✐❞✉❛❧s

❛♥❞ t❤❡✐r ✐♥t❡r❛❝t✐♦♥ ✇✐t❤ t❤❡ ❡♥✈✐r♦♥♠❡♥t ❛♥❞ ✇✐t❤ ❡❛❝❤ ♦t❤❡r✳ ❙✐♥❝❡ t❤❡ ✐♥❞✐✲

✈✐❞✉❛❧s ❛r❡ r❡♣r❡s❡♥t❡❞ ❡①♣❧✐❝✐t❧② ✐♥ t❤❡ ♠♦❞❡❧✱ t❤❡ ✐♥❤❡r❡♥t ❤❡t❡r♦❣❡♥❡✐t② ♦❢ t❤❡

♣♦♣✉❧❛t✐♦♥ ❝❛♥ ❜❡ r❡❛❞✐❧② ❛❝❝♦✉♥t❡❞ ❢♦r ❜② ❡①♣❧✐❝✐t❧② ♠♦❞❡❧✐♥❣ ❧♦❝❛❧ ❞✐✛❡r❡♥❝❡s ✐♥

t❤❡ ❡♥✈✐r♦♥♠❡♥t ❛♥❞ ❜❡t✇❡❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❬▼✉r♣❤② ✷✵✵✽❪ ❬❑r❡❢t ✶✾✾✾❪✳ ●r✐♠♠

❬●r✐♠♠ ✶✾✾✾❪ ❞❡✜♥❡s ■❇▼s ✐♥ t❤❡ ❡❝♦❧♦❣✐❝❛❧ ❝♦♥t❡①t ❛s ✑ s✐♠✉❧❛t✐♦♥ ♠♦❞❡❧s t❤❛t

tr❡❛t ✐♥❞✐✈✐❞✉❛❧s ❛s ✉♥✐q✉❡ ❛♥❞ ❞✐s❝r❡t❡ ❡♥t✐t✐❡s ✇❤✐❝❤ ❤❛✈❡ ❛t ❧❡❛st ♦♥❡ ♣r♦♣❡rt②

✐♥ ❛❞❞✐t✐♦♥ t♦ ❛❣❡ t❤❛t ❝❤❛♥❣❡s ❞✉r✐♥❣ t❤❡ ❧✐❢❡ ❝②❝❧❡✑✳ ❙✐♥❝❡ ♠✐❝r♦❜❡ ♠♦❞❡❧s ❞♦

♥♦t ✐♥❝❧✉❞❡ ❛❣❡ ✭r❛t❤❡r s✐③❡✮ t❤❡ ❞❡✜♥✐t✐♦♥ ✐s ✉s✉❛❧❧② r❡❧❛①❡❞ t♦ ✐♥❝❧✉❞❡ ❛t ❧❡❛st

t✇♦ ✐♥❞❡♣❡♥❞❡♥t ♣r♦♣❡rt✐❡s ✭♥♦t ❝♦✉♥t✐♥❣ ♣♦s✐t✐♦♥✮ ❬❍❡❧❧✇❡❣❡r ✷✵✵✾❪✳ ❍♦✇❡✈❡r✱ s❡✈✲

❡r❛❧ ❜♦tt♦♠✲✉♣ ♠♦❞❡❧s ✉s❡❞ ✐♥ ❡❝♦❧♦❣② t❤❛t ❞♦ ♥♦t ❡♥t✐r❡❧② s❛t✐s❢② t❤✐s ❞❡✜♥✐t✐♦♥

❛r❡ st✐❧❧ r❡❢❡rr❡❞ t♦ ❛s ■❇▼ ❛s ❧♦♥❣ ❛s t❤❡② tr❡❛t ✐♥❞✐✈✐❞✉❛❧s ❛s ❞✐s❝r❡t❡ ❡♥t✐t✐❡s

❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪✳

❆ s✉r✈❡② ♦❢ t❤❡ ❧✐t❡r❛t✉r❡ ♦♥ t❤❡ ✉s❡ ♦❢ ■❇▼s ✐♥ ♠✐❝r♦❜✐❛❧ ❡❝♦❧♦❣②

s❤♦✇s t❤❛t t❤❡ ❛♣♣r♦❛❝❤ ✐s ❣❛✐♥✐♥❣ ❛ ❝❡rt❛✐♥ ❛❝❝❡♣t❛♥❝❡ ❛♠♦♥❣ ♠✐❝r♦❜✐♦❧✲

♦❣✐sts ✭s❡❡ ❬❍❡❧❧✇❡❣❡r ✷✵✵✾❪ ❬❋❡rr❡r ✷✵✵✽❪ ❢♦r ❛ r❡✈✐❡✇✮✳ ■❇▼ ❛♣♣r♦❛❝❤ ❤❛s

❜❡❡♥ ❛♣♣❧✐❡❞ ❢♦r ♠♦❞❡❧✐♥❣ ❜❛❝t❡r✐❛ s②st❡♠s t❤❛t ❛r✐s❡ ✐♥ ✇❛st❡✇❛t❡r tr❡❛t♠❡♥t

♣❧❛♥ts ❬❑r❡❢t ✷✵✵✶❪ ❬●✉❥❡r ✷✵✵✷❪❬P✐❝✐♦r❡❛♥✉ ✷✵✵✹❪❬P✐❝✐♦r❡❛♥✉ ✷✵✵✺❪ ❬❳❛✈✐❡r ✷✵✵✺❪✱

♠❡❞✐❝❛❧ ❛♥❞ ✐♥❞✉str✐❛❧ s❡tt✐♥❣s✱ ❜❛❝t❡r✐❛ ✐♥ ❢♦♦❞ ❛♥❞ ♦t❤❡r ❡♥✈✐r♦♥♠❡♥ts

❬●✐♥♦✈❛rt ✷✵✵✷❪❬❉❡♥s ✷✵✵✺❪❬❊♠♦♥❡t ✷✵✵✺❪✳ ❍❡❧❧✇❡❣❡r ❛♥❞ ❇✉❝❝✐ ❬❍❡❧❧✇❡❣❡r ✷✵✵✾❪ r❡✲

✈✐❡✇❡❞ ✹✻ ♣✉❜❧✐s❤❡❞ ♣❛♣❡rs ❞❡❛❧✐♥❣ ✇✐t❤ ■❇▼ ❛♣♣❧✐❝❛t✐♦♥ ❢♦r ♠✐❝r♦❜✐❛❧ ❛♥❞ ♣❤②t♦✲

♣❧❛♥❦t♦♥ s②st❡♠s✳ ❚❤❡② ♥♦t✐❝❡❞ t❤❛t t❤❡ ✉s❡ ♦❢ ■❇▼ ❛♣♣r♦❛❝❤ ✐s ♦❢t❡♥ ♠♦t✐✈❛t❡❞

❜② t❤❡ ✐♠♣♦rt❛♥❝❡ ♦❢ t❤❡ ♣♦♣✉❧❛t✐♦♥ ❤❡t❡r♦❣❡♥❡✐t②✭46%✮✱ ❡♠❡r❣❡♥❝❡ ♦❢ ♣♦♣✉❧❛t✐♦♥

❧❡✈❡❧ ♣❛tt❡r♥s ✭24%✮✱ ❞✐s❝r❡t❡♥❡ss ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✭5%✮ ❛♥❞ ♦t❤❡r r❡❛s♦♥s ✭26%✮

❬❍❡❧❧✇❡❣❡r ✷✵✵✾❪✳ ❚❤❡ r❛♣✐❞❧② ❣r♦✇✐♥❣ ✐♥t❡r❡st ✐♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✐♥❣

❛♣♣r♦❛❝❤ ✐s t♦ ❛ ♠❛❥♦r ♣❛rt ❡♥❝♦✉r❛❣❡❞ ❜② t❤❡ r❛♣✐❞ ✐♥❝r❡❛s❡ ✐♥ ❝♦♠♣✉t✐♥❣ ♣♦✇❡r

❛♥❞ ❛❞✈❛♥❝❡s ✐♥ ♠♦❧❡❝✉❧❛r ❜✐♦❧♦❣②✱ ❜✐♦❝❤❡♠✐str② ❛♥❞ ❝♦♥❢♦❝❛❧ ♠✐❝r♦s❝♦♣② ❞✉r✐♥❣

t❤❡ ❧❛st ✷✵ ②❡❛rs✳ P♦✇❡r❢✉❧ ❝♦♠♣✉t❡rs ♠❛❦❡ ✐t ♣r❛❝t✐❝❛❧ t♦ s✐♠✉❧❛t❡ ❧❛r❣❡ ♥✉♠✲

❜❡rs ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐♥ ✈✐rt✉❛❧ ❡♥✈✐r♦♥♠❡♥ts ✇❤✐❧❡ t❤❡ ♥❡✇ ❡①♣❡r✐♠❡♥t❛❧ t♦♦❧s ✉s❡❞

✐♥ ♠✐❝r♦❜✐♦❧♦❣② ♣r♦✈✐❞❡ ❛ ❞❡t❛✐❧❡❞ ♦❜s❡r✈❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❧❡✈❡❧ ❞②♥❛♠✐❝s ❛♥❞

r❛✐s❡s ♥❡✇ q✉❡st✐♦♥s ❛❜♦✉t t❤❡ ❢✉♥❝t✐♦♥✐♥❣ ❛♥❞ ♦r❣❛♥✐③❛t✐♦♥ ♦❢ ♠✐❝r♦❜✐❛❧ ❡❝♦s②s✲

Page 16: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✳✸✳ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧✐♥❣ ♦❢ ♠✐❝r♦❜✐❛❧ ❡❝♦s②st❡♠s ✸

t❡♠s✳ ❊①❛♠♣❧❡s ✐♥❝❧✉❞❡ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢ t❤❡ ❝♦♠♣❧❡① str✉❝t✉r❡ ♦❢ ♠✐❝r♦❜✐❛❧

❜✐♦✜❧♠s ❛s r❡✈❡❛❧❡❞ ❜② ❝♦♥❢♦❝❛❧ ♠✐❝r♦s❝♦♣② ♦❜s❡r✈❛t✐♦♥s ❛♥❞ ✐♥✈❡st✐❣❛t❡❞ ✉s✐♥❣

■❇▼s ❬❑r❡❢t ✷✵✵✶❪❬P✐❝✐♦r❡❛♥✉ ✷✵✵✹❪ ♦r t❤❡ ❛❞❛♣t❛t✐✈❡ ❛♥❞ ❝♦❧❧❛❜♦r❛t✐♥❣ str❛t❡❣✐❡s ♦❢

t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ t❤❡✐r ✐♠♣❛❝t ♦♥ t❤❡ ♣♦♣✉❧❛t✐♦♥ ❧❡✈❡❧ ❞②♥❛♠✐❝s ❬❱❧❛❝❤♦s ✷✵✵✻❪✳

❆❧t❤♦✉❣❤ ■❇▼s ❡♥❥♦②❡❞ t❤❡ ❝❧❛✐♠ ♦❢ t❤❡ ❧❛t❡st ❣❡♥❡r❛t✐♦♥ ♠♦❞❡❧s t❤❡② ❢❛❝❡ ❝r✐t✐✲

❝✐s♠ ❛s ✇❡❧❧ ❬▲❛s♣✐❞♦✉ ✷✵✵✾❪✳ ❙♦♠❡ ♦❢ t❤❡ ❞r❛✇❜❛❝❦s ♦❢ t❤❡ ■❇▼ ❛♣♣r♦❛❝❤ ❛r❡ s✐♠♣❧②

❞✉❡ t♦ t❤❡ r❡❧❛t✐✈❡❧② ②♦✉♥❣ ❛❣❡ ♦❢ t❤❡ ❛♣♣r♦❛❝❤ ✇❤✐❝❤ st✐❧❧ ♠✐ss❡s ❛ s♦❧✐❞ ♠❡t❤♦❞♦❧♦❣✲

✐❝❛❧ ❢r❛♠❡✇♦r❦ ❢♦r ❞❡✈❡❧♦♣✐♥❣✱ ✐♠♣❧❡♠❡♥t✐♥❣ ❛♥❞ ✈❛❧✐❞❛t✐♥❣ ■❇▼s✳ ❚❤❡s❡ ✐ss✉❡s ❤❛✈❡

❜❡❡♥ ❛❞❞r❡ss❡❞ ❜② s❡✈❡r❛❧ r❡❝❡♥t t❡①t❜♦♦❦s t❤❛t ♣r♦♣♦s❡❞ ❣✉✐❞❡❧✐♥❡s ❢♦r ❜✉✐❧❞✐♥❣ ❛♥❞

✉s✐♥❣ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ❬●r✐♠♠ ✷✵✵✻❪❬❚r❡✉✐❧ ✷✵✵✽❪✳ ❖t❤❡r ❧✐♠✐t❛t✐♦♥s ❤♦✇❡✈❡r ❛r❡ ✐♥✲

❤❡r❡♥t t♦ t❤❡ ♥❛t✉r❡ ♦❢ t❤❡ ■❇▼s ❛s st♦❝❤❛st✐❝ s✐♠✉❧❛t✐♦♥ ♠♦❞❡❧s✳ ■❇▼s ✉s❡❞ ✐♥

❡❝♦❧♦❣② ♦❢t❡♥ ❡♥❝♦♠♣❛ss t❤❡ r❛♥❞♦♠♥❡ss ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❧❡✈❡❧ ✐♥t❡r❛❝t✐♦♥s ❛♥❞ ❡✈♦❧✈❡

✐♥ ❛ ❧❛r❣❡ st❛t❡ ❛♥❞ ♣❛r❛♠❡t❡r s♣❛❝❡ t❤❛t ❝❛♥ ♦♥❧② ❜❡ s❛♠♣❧❡❞✳ ❚❤❡ ❝♦♠♣❧❡①✐t②

❛♥❞ ❧✐♠✐t❡❞ ❣❡♥❡r❛❧✐t② ❛r❡ ♦❢t❡♥ q✉♦t❡❞ ❛s t❤❡ ♠❛✐♥ ❧✐♠✐t❛t✐♦♥s ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧✐♥❣ ❬❯❝❤♠❛♥s❦✐ ✶✾✾✻❪✳ ●r✐♠♠ ♥♦t✐❝❡❞ t❤❛t ■❇▼s ✉s✉❛❧❧② ♠❛❦❡ ♠♦r❡ r❡❛❧✐s✲

t✐❝ ❛ss✉♠♣t✐♦♥s t❤❛♥ s✐♠♣❧❡ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s✱ ❜✉t ✐t s❤♦✉❧❞ ♥♦t ❜❡

❢♦r❣♦tt❡♥ t❤❛t t❤❡ ❛✐♠ ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✐♥❣ ✐s ♥♦t ❵r❡❛❧✐s♠✬ ❜✉t ♠♦❞❡❧✐♥❣

❛♥❞ t❤❛t ♠♦❞❡❧✐♥❣ ♠✉st ❜❡ ❣✉✐❞❡❞ ❜② ❛ ♣r♦❜❧❡♠ ♦r q✉❡st✐♦♥ ❛❜♦✉t ❛ r❡❛❧ s②st❡♠✱

♥♦t ❥✉st ❜② t❤❡ s②st❡♠ ✐ts❡❧❢ ❬●r✐♠♠ ✷✵✵✻❪✳

✶✳✸ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧✐♥❣ ♦❢ ♠✐❝r♦❜✐❛❧

❡❝♦s②st❡♠s

❚r❛❞✐t✐♦♥❛❧❧②✱ ♠✐❝r♦❜✐❛❧ s②st❡♠s ❛r❡ ♠♦❞❡❧❡❞ ✉s✐♥❣ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞✲

❡❧s✳ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ♦❢t❡♥ t❛❦❡ t❤❡ ❢♦r♠ ♦❢ ❛ s❡t ♦❢ ❞✐✛❡r❡♥t✐❛❧ ❛♥❞

♣❛rt✐❛❧ ❞✐✛❡r❡♥t✐❛❧ ❡q✉❛t✐♦♥s t❤❛t ❞❡s❝r✐❜❡ t❤❡ ❞②♥❛♠✐❝ ♦❢ ❛❣❣r❡❣❛t❡❞ s②st❡♠✲❧❡✈❡❧

st❛t❡ ✈❛r✐❛❜❧❡s✳ ❚❤❡ ♥♦t✐♦♥ ♦❢ ❛❣❣r❡❣❛t❡❞ st❛t❡ ✈❛r✐❛❜❧❡ ✐♠♣❧✐❡s s♦♠❡ ❛✈❡r❛❣✐♥❣ ♦r

❣r♦✉♣✐♥❣ ♦❢ t❤❡ ♠✐❝r♦s❝❛❧❡ ✈❛r✐❛❜❧❡s ♦❢ ❛ s②st❡♠✳ ❋♦r ✐♥st❛♥❝❡ ❛ s②st❡♠ ❢♦r♠❡❞ ✇✐t❤

N ❞✐s❝r❡t❡ ✐♥❞✐✈✐❞✉❛❧s ❡❛❝❤ ❝❤❛r❛❝t❡r✐③❡❞ ❜② ❛ r❡❛❧✲✈❛❧✉❡❞ st❛t❡ ✈❛r✐❛❜❧❡Xi✱ i = 1..N

✐s ❡♥t✐r❡❧② ❞❡s❝r✐❜❡❞ ❜② t❤❡ ✈❡❝t♦r (Xi)i=1..N ✳ ❆♥ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧

♦❢ t❤✐s s②st❡♠s ✐♠♣❧✐❡s t❤❡ r❡❞✉❝t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ t♦ ❛ s♠❛❧❧❡r

s②st❡♠ ❞❡s❝r✐❜❡❞ ✇✐t❤ ♥❡✇ ✭❛❣❣r❡❣❛t❡❞✮ ✈❛r✐❛❜❧❡s Yj ✱ j = 1..M ✇✐t❤ M << N ✳

❚❤❡ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ ✐s t❤❡♥ ❢♦r♠❡❞ ✇✐t❤ t❤❡ s❡t ♦❢ ❞✐✛❡r❡♥t✐❛❧ ✭♦r

♣❛rt✐❛❧ ❞✐✛❡r❡♥t✐❛❧✮ ❡q✉❛t✐♦♥s ♦❢ t❤❡ ✈❛r✐❛❜❧❡s Yj ✇✐t❤ t❤❡ ❛♣♣r♦♣r✐❛t❡ ❜♦✉♥❞❛r② ❛♥❞

✐♥✐t✐❛❧ ❝♦♥❞✐t✐♦♥s✳

❆ ❣❡♥❡r✐❝ ❡①❛♠♣❧❡ ♦❢ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ✉s❡❞ ✐♥ ♠✐❝r♦❜✐❛❧ ❡❝♦❧♦❣②

❝❛♥ ❜❡ ❞❡r✐✈❡❞ ❢♦r ❛ s✐♠♣❧❡ s②st❡♠ ❢♦r♠❡❞ ✇✐t❤ N ✐♥❞✐✈✐❞✉❛❧s ❡❛❝❤ ❝❤❛r❛❝t❡r✐③❡❞

✇✐t❤ ❛ ♠❛ss mi✱ i = 1..N ✳ ❘❛t❤❡r t❤❛♥ tr❛❝❦✐♥❣ t❤❡ ❞②♥❛♠✐❝s ♦❢ ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧ ♦♥❡

❝❛♥ ❞❡✜♥❡ ❛ ♥❡✇ ❛❣❣r❡❣❛t❡❞ ✈❛r✐❛❜❧❡ Yj ✱ j = 1 ❝♦rr❡s♣♦♥❞✐♥❣ t♦ t❤❡ t♦t❛❧ ♠❛ss ♦❢

t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ ❞❡r✐✈❡ ❛ ❞✐✛❡r❡♥t✐❛❧ ❡q✉❛t✐♦♥ t❤❛t ❞❡s❝r✐❜❡ t❤❡ ❞②♥❛♠✐❝s ♦❢ t❤✐s

Page 17: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✹ ❈❤❛♣t❡r ✶✳ ■♥tr♦❞✉❝t✐♦♥

✈❛r✐❛❜❧❡✳ ❚❤❡ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ t❤❡♥ t❛❦❡s t❤❡ ❢♦r♠ ♦❢ ❛ ❞✐✛❡r❡♥t✐❛❧

❡q✉❛t✐♦♥✿

dY

dt= Φ(Y )Y ✭✶✳✶✮

❲❤❡r❡ φ(Y ) ✐s ❛ ❢✉♥❝t✐♦♥ t❤❛t ❞❡s❝r✐❜❡s t❤❡ ♥❡t ❣r♦✇t❤ r❛t❡ ♦❢ t❤❡ ♣♦♣✉❧❛t✐♦♥✳

❊q✉❛t✐♦♥s ♦❢ t❤✐s ❦✐♥❞ st✐❧❧ ♣❧❛② s✉❝❤ ❛ ❝❡♥tr❛❧ r♦❧❡ ✐♥ ♠✐❝r♦❜✐❛❧ ❡❝♦❧♦❣②✱ t❤❛t ♠❛♥②

s✉❜s❡q✉❡♥t ❡❧❛❜♦r❛t✐♦♥s ♦❢ t❤❡♦r② ❤❛✈❡ t❛❦❡♥ t❤❡♠ ❛s t❤❡ st❛rt✐♥❣ ♣♦✐♥t✳ ❘❡s♦✉r❝❡

❞②♥❛♠✐❝s ❛♥❞ s♣❛t✐❛❧ ✈❛r✐❛t✐♦♥ ❝❛♥ ❜❡ ✐♥tr♦❞✉❝❡❞ ❛♥❞ t❤❡ ♠♦❞❡❧s ❛r❡ s♦♠❡t✐♠❡s

✐♥t❡r♣r❡t❡❞ ❛s r❡❢❡rr✐♥❣ t♦ ✐♥❞✐✈✐❞✉❛❧s ❜② ❛ss✉♠✐♥❣ t❤❛t t❤❡ ❢✉♥❝t✐♦♥ Φ(Y ) ❛❧s♦ ❞❡✲

s❝r✐❜❡s t❤❡ ✐♥t❡r❛❝t✐♦♥s ❛t t❤❡ ❧❡✈❡❧ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❬▼❝❑❛♥❡ ✷✵✵✹❪✳ ❍♦✇❡✈❡r ✐♥

♠♦st s✐t✉❛t✐♦♥s t❤❡s❡ ♠♦❞❡❧s ❛r❡ ❣❡♥❡r❛❧❧② ❞❡r✐✈❡❞ ✇✐t❤♦✉t t❤❡ ♥❡❡❞ ♦❢ ❛ ❞❡t❛✐❧❡❞

❦♥♦✇❧❡❞❣❡ ♦❢ t❤❡ ✐♥t❡r❛❝t✐♦♥s ❜❡t✇❡❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ r❡❧② ✐♥st❡❛❞ ♦♥ t❤❡ ❛s✲

s✉♠♣t✐♦♥ t❤❛t t❤❡ t❡r♠s ✇❤✐❝❤ ❛r✐s❡ ✐♥ t❤❡ ❣♦✈❡r♥✐♥❣ ❡q✉❛t✐♦♥s r❡♣r❡s❡♥t t❤❡ ♥❡t

❡✛❡❝ts ♦❢ ✐♥❞✐✈✐❞✉❛❧ ✐♥t❡r❛❝t✐♦♥s ✐♥ s♦♠❡ ❣❡♥❡r✐❝ ✇❛② ❬▼❝❑❛♥❡ ✷✵✵✹❪✳

❚❤❡ r❡❧❛t✐✈❡ s✐♠♣❧✐❝✐t② ❛♥❞ ❣❡♥❡r✐❝✐t② ♦❢ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❢r♦♠

♦♥❡ s✐❞❡ ❛♥❞ t❤❡ ❛✈❛✐❧❛❜✐❧✐t② ♦❢ ❛ s♦❧✐❞ ♠❛t❤❡♠❛t✐❝❛❧ ❛♥❞ ♥✉♠❡r✐❝❛❧ ❢r❛♠❡✇♦r❦

t♦ ❛♥❛❧②③❡ t❤❡♠ ♦♥ t❤❡ ♦t❤❡r s✐❞❡ ❤❛✈❡ ❝♦♥tr✐❜✉t❡❞ t♦ t❤❡✐r s✉❝❝❡ss❢✉❧ ❡st❛❜❧✐s❤✲

♠❡♥t ❛s ❛ st❛♥❞❛r❞ ❢♦r ♠♦❞❡❧✐♥❣ ❡❝♦❧♦❣✐❝❛❧ s②st❡♠s✳ ❆❞❞✐t✐♦♥❛❧❧②✱ ❢♦r ❞❡❝❛❞❡s ♠✐✲

❝r♦❜✐❛❧ ❡❝♦❧♦❣② str✉❣❣❧❡❞ ❛s ❛ s❝✐❡♥t✐✜❝ ❞✐s❝✐♣❧✐♥❡ ❜❡❝❛✉s❡ ♦❢ t❤❡ ❧❛❝❦ ♦❢ r❡❧✐❛❜❧❡

❡①♣❡r✐♠❡♥t❛❧ t♦♦❧s t♦ ♦❜s❡r✈❡ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❧❡✈❡❧ str✉❝t✉r❡ ♦❢ ♠✐❝r♦❜✐❛❧ ❡❝♦s②s✲

t❡♠s✳ ▼✐❝r♦❜❡s ✇❡r❡ ♦❜s❡r✈❡❞ ❛♥❞ q✉❛♥t✐✜❡❞ ♠❛✐♥❧② ❛t t❤❡ ♣♦♣✉❧❛t✐♦♥ ❧❡✈❡❧

❬❍❡❧❧✇❡❣❡r ✷✵✵✾❪❬❇r❡❤♠✲❙t❡❝❤❡r ✷✵✵✹❪✳ ❋♦r ❡①❛♠♣❧❡ t❤❡ ❜❛❝t❡r✐❛ ✐♥ ❛ ✇❛st❡✇❛t❡r

tr❡❛t♠❡♥t ❜✐♦r❡❛❝t♦r ✇❡r❡ q✉❛♥t✐✜❡❞ ❜② ♠❡❛s✉r✐♥❣ t❤❡ ✈♦❧❛t✐❧❡ s✉s♣❡♥❞❡❞ s♦❧✐❞s✳

❚❤✉s✱ s✐♠♣❧❡ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ✇❡r❡ s✉✣❝✐❡♥t t♦ ❡①♣❧♦✐t s✉❝❤ ❞❛t❛✳

✶✳✹ ❉❡❜❛t❡ ❜❡t✇❡❡♥ ■❇▼ ❛♥❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧✐♥❣

❚❤❡r❡ ✐s st✐❧❧ ❛♥ ♦♥❣♦✐♥❣ ❞❡❜❛t❡ ✐♥ ❡❝♦❧♦❣② ❜❡t✇❡❡♥ t❤♦s❡ ❢❛✈♦r✐♥❣ s✐♠♣❧❡ s②st❡♠✲

❧❡✈❡❧ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❝♦♥t❛✐♥✐♥❣ ♦♥❧② ❛ ❢❡✇ ❡q✉❛t✐♦♥s ❡①♣r❡ss✐♥❣ ❛ s♠❛❧❧ ♥✉♠✲

❜❡r ♦❢ ❣❡♥❡r❛❧ ♣r✐♥❝✐♣❧❡s ❛♥❞ t❤♦s❡ ♣r❡❢❡rr✐♥❣ ❝♦♠♣❧❡① s✐♠✉❧❛t✐♦♥ ♠♦❞❡❧s t❤❛t ❛r❡

♠♦r❡ ✑str✉❝t✉r❛❧❧② r❡❛❧✐st✐❝✑ ✇✐t❤ ❛ ♠♦r❡ ❞❡t❛✐❧❡❞ r❡♣r❡s❡♥t❛t✐♦♥s ♦❢ t❤❡ ❜❛s✐❝ ♣r♦✲

❝❡ss❡s ❛♥❞ ✐♥t❡r❛❝t✐♦♥s ❞❡t❡r♠✐♥✐♥❣ t❤❡ s②st❡♠ ❞②♥❛♠✐❝ ❬❆✉♠❛♥♥ ✷✵✵✼❪✳ ●r✐♠♠

❬●r✐♠♠ ✷✵✵✺❪ ♥♦t✐❝❡❞ t❤❛t str❡♥❣t❤s ❛♥❞ ✇❡❛❦♥❡ss ♦❢ ■❇▼s ❛♥❞ s②st❡♠✲❧❡✈❡❧ ♠❛t❤✲

❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❛r❡ t♦ ❛ ❧❛r❣❡ ❞❡❣r❡❡ ✐♥✈❡rs❡❧② r❡❧❛t❡❞✳ ▼❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❛r❡

tr❛♥s♣❛r❡♥t ❛♥❞ ❡❛s② t♦ ❝♦♠♠✉♥✐❝❛t❡ ❛s t❤❡② ❛r❡ ❜② ❞❡✜♥✐t✐♦♥✱ ❢♦r♠✉❧❛t❡❞ ✐♥ t❤❡

✉♥✐✈❡rs❛❧ ❛♥❞ ✉♥❛♠❜✐❣✉♦✉s ❧❛♥❣✉❛❣❡ ♦❢ ♠❛t❤❡♠❛t✐❝s✳ ❚❤❡② ❝❛♥ ♠❛❦❡ ♣r❡❞✐❝t✐♦♥s✱

r❡q✉✐r❡ ❧❡ss ❞❛t❛ ❢♦r ♣❛r❛♠❡t❡r ❡st✐♠❛t✐♦♥ ❛♥❞ ♠♦❞❡❧ ✈❛❧✐❞❛t✐♦♥✱ ♠❛② ❜❡ ❧❡ss ♣r♦♥❡

t♦ ❡rr♦r ♣r♦♣❛❣❛t✐♦♥ ❛♥❞ s✐♥❝❡ t❤❡② ❡♠❜♦❞② ♦♥❧② ❛ ❢❡✇ ❤❡✉r✐st✐❝ ♣r✐♥❝✐♣❧❡s✱ ♠❛② ❜❡

❧✐❦❡❧② t♦ ❧❡❛❞ t♦ ❣❡♥❡r❛❧ ❝❛✉s❛❧ ✉♥❞❡rst❛♥❞✐♥❣ ❬❆✉♠❛♥♥ ✷✵✵✼❪✳ ▼❛t❤❡♠❛t✐❝❛❧ ♠♦❞✲

❡❧s✱ ❤♦✇❡✈❡r✱ ❤❛✈❡ ✈❡r② ❧✐♠✐t❡❞ ❛❜✐❧✐t② t♦ ❛♥s✇❡r q✉❡st✐♦♥ ❛❜♦✉t ❤♦✇ s②st❡♠ ❧❡✈❡❧

❜❡❤❛✈✐♦r ❡♠❡r❣❡ ♦✉t ♦❢ ❧♦❝❛❧ ✐♥t❡r❛❝t✐♦♥s✳ ❖♥ t❤❡ ♦t❤❡r ❤❛♥❞✱ ■❇▼s ❛r❡ ❞❡s✐❣♥❡❞

Page 18: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✳✺✳ ❚❤❡s✐s s❝♦♣❡ ✺

t♦ ❛♥s✇❡r s✉❝❤ q✉❡st✐♦♥s ❜② ❡①♣❧✐❝✐t❧② r❡♣r❡s❡♥t✐♥❣ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ t❤❡✐r ✐♥t❡r✲

❛❝t✐♦♥s✳ ❚❤❡② ♦❢t❡♥ ❡♥❝♦♠♣❛ss t❤❡ r❛♥❞♦♠♥❡ss ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❧❡✈❡❧ ✐♥t❡r❛❝t✐♦♥s ❛♥❞

t❤✉s ②✐❡❧❞ r❡❛❧✐st✐❝ s②st❡♠✲❧❡✈❡❧ ♣❛tt❡r♥s✳ ❍♦✇❡✈❡r✱ ♦♥❡ ❝♦♥s❡q✉❡♥❝❡ ♦❢ ■❇▼s ❜❡✐♥❣

❧❡ss s✐♠♣❧❡ t❤❛♥ ❝❧❛ss✐❝❛❧ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ✐s t❤❛t ■❇▼s ❛r❡ ♥♦t ❡❛s② t♦ ❝♦♠✲

♠✉♥✐❝❛t❡✱ ❛♥❛❧②③❡ ❛♥❞ ❧❡❛r♥ ❢r♦♠ ❬●r✐♠♠ ✷✵✵✺❪✳ ■❇▼s ❡✈♦❧✈❡ ✐♥ ❛ ❧❛r❣❡ ♣❛r❛♠❡t❡r

st❛t❡ s♣❛❝❡ ✇❤✐❝❤ ❝❛♥ ♦♥❧② ❜❡ s❛♠♣❧❡❞ ❬▼✉rr❡❧❧ ✷✵✵✵❪✳ ❈♦♥s❡q✉❡♥t❧② ✐t ✐s ❣❡♥❡r❛❧❧②

♥♦t ❦♥♦✇♥ t♦ ✇❤❛t ❡①t❡♥t t❤❡ ♦✉t❝♦♠❡ ♦❜t❛✐♥❡❞ ❢♦r ❛ s❡t ♦❢ ♣❛r❛♠❡t❡rs ❤♦❧❞s ❢♦r

♦t❤❡r s❡ts ❬▼✉rr❡❧❧ ✷✵✵✵❪✳ ❋✉rt❤❡r♠♦r❡✱ ✐❢ t❤❡ s✐♠✉❧❛t✐♦♥s ❛r❡ st♦❝❤❛st✐❝✱ t❤❡ ❡❝♦✲

❧♦❣✐❝❛❧ s✐❣♥❛❧ ♠❛② ♦♥❧② ❡♠❡r❣❡ ❛❢t❡r ❛✈❡r❛❣✐♥❣ ♦✈❡r ❛ s❡r✐❡s ♦❢ r❡❛❧✐③❛t✐♦♥s✱ ❡✈❡♥

✇✐t❤ ❛ ♣❛rt✐❝✉❧❛r ♣❛r❛♠❡t❡r s❡t✱ ✇❤✐❝❤ ♠❛② ❜❡❝♦♠❡ ❝♦♠♣✉t❛t✐♦♥❛❧❧② ✈❡r② ❡①♣❡♥s✐✈❡

❬▼✉rr❡❧❧ ✷✵✵✵❪✳ ■❇▼ ❛❞✈♦❝❛t❡ ❤♦✇❡✈❡r ❝❧❛✐♠s t❤❛t t❤❡ ❛♣♣r♦❛❝❤ ✐s ♠♦r❡ t❤❛♥ ❛

♥❡✇ t♦♦❧ t❤❛t ❛❞❞s t♦ t❤❡ t♦♦❧❜♦① ♦❢ ❡❝♦❧♦❣✐sts✱ ❜✉t ❤❛❞ ❛ s✐❣♥✐✜❝❛♥t ✐♠♣❧✐❝❛t✐♦♥ ♦♥

t❤❡ ✇❛② ✇❡ ❧♦♦❦ t♦ t❤❡s❡ ❝♦♠♣❧❡① s②st❡♠✳ ❇② ✉s✐♥❣ ■❇▼s t❤❡ ❢♦❝✉s ✐s s❤✐❢t❡❞ ❢r♦♠

♣♦♣✉❧❛t✐♦♥s t♦ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ s❡✈❡r❛❧ ■❇▼s ❤❛✈❡ ❞❡♠♦♥str❛t❡❞ t❤❡ ♣♦t❡♥t✐❛❧ s✐❣♥✐✜✲

❝❛♥❝❡ ♦❢ ✐♥❞✐✈✐❞✉❛❧ ❝❤❛r❛❝t❡r✐st✐❝s t♦ ♣♦♣✉❧❛t✐♦♥ ❞②♥❛♠✐❝s ❛♥❞ ❡❝♦s②st❡♠s ♣r♦❝❡ss❡s

❬●r✐♠♠ ✷✵✵✺❪✳

✶✳✺ ❚❤❡s✐s s❝♦♣❡

■♥ t❤✐s t❤❡s✐s✱ ✇❡ ♠♦✈❡ ❜❡②♦♥❞ t❤❡ ❞❡❜❛t❡ ♦❢ ✇❤❡t❤❡r ♦❢ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s

♦r ■❇▼s ❛r❡ ♠♦r❡ ❛♣♣r♦♣r✐❛t❡ ❢♦r r❡♣r❡s❡♥t✐♥❣ ♠✐❝r♦❜✐❛❧ ❡❝♦s②st❡♠s✱ ❛♥❞ ❝♦♥❝❡♥✲

tr❛t❡ ♦♥ ❤♦✇ t❤❡ ❜❡♥❡✜ts ♦❢ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❝❛♥ ❜❡ ❝♦♠❜✐♥❡❞ ✇✐t❤

str❡♥❣t❤s ♦❢ ■❇▼s✳ ❲❡ ❛❞♦♣t ❛ ✑❞♦✉❜❧❡✲♠♦❞❡❧✐♥❣✑ str❛t❡❣② ❬❉❡✛✉❛♥t ✷✵✵✹❪ ❜② ✉s✐♥❣

♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❛❧♦♥❣ ✇✐t❤ ■❇▼s ✐♥ ♠♦❞❡❧✐♥❣ ♠✐❝r♦❜✐❛❧ s②st❡♠s✳ ❙✉❝❤ ❛♥ ❛♣✲

♣r♦❛❝❤ ❝❛♥ ❤❡❧♣ ❜r✐❞❣✐♥❣ t❤❡ ♣❡r❝❡✐✈❡❞ ❣❛♣ ❜❡t✇❡❡♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ❛♥❞ ❝❧❛ss✐❝❛❧

❛♣♣r♦❛❝❤❡s t♦ ♠✐❝r♦❜✐❛❧ s②st❡♠ ♠♦❞❡❧✐♥❣✳ ❲❡ ♣r♦✈✐❞❡ s✐♠♣❧❡ ✐❧❧✉str❛t✐♦♥s ♦❢ ❤♦✇

♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❝❛♥ ❜❡ ✉s❡❞ t♦ ❛♥❛❧②③❡ ❛♥❞ ❛♣♣r♦①✐♠❛t❡ t❤❡ ❞②♥❛♠✐❝ ♦❢ ■❇▼s

♦❢ ♠✐❝r♦❜✐❛❧ s②st❡♠s ❛♥❞ ❛ss❡ss t❤❡✐r ♣♦t❡♥t✐❛❧ ❛♥❞ ❧✐♠✐ts ✐♥ r❡♣r♦❞✉❝✐♥❣ t❤❡ r✐❝❤

❛♥❞ ❝♦♠♣❧❡① ❞②♥❛♠✐❝ ♦❢ t❤❡ ■❇▼✳

❲❡ ❝♦♥s✐❞❡r ❛♥ ■❇▼ ❛s ✑❛ ✈✐rt✉❛❧ ❡①♣❡r✐♠❡♥t❛❧ s②st❡♠✑ ❞❡s✐❣♥❡❞ t♦ ❡♥❝♦♠♣❛ss t❤❡

❝♦♠♣❧❡①✐t② ♦❢ ❛ ♠✐❝r♦❜✐❛❧ s②st❡♠ ❜② ✐♥❝❧✉❞✐♥❣ ❢❡❛t✉r❡s ❧✐❦❡ t❤❡ ❞✐s❝r❡t❡♥❡ss ♦❢ t❤❡

✐♥❞✐✈✐❞✉❛❧s✱ t❤❡ st♦❝❤❛st✐❝✐t② ♦❢ t❤❡✐r ✐♥t❡r❛❝t✐♦♥s✱ t❤❡ ❤❡t❡r♦❣❡♥❡✐t② ♦❢ t❤❡✐r tr❛✐ts

❛♥❞ t❤❡ ❤❡t❡r♦❣❡♥❡✐t② ♦❢ t❤❡✐r ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t✳ ❖♥❝❡ ❝♦♥str✉❝t❡❞ ❛♥ ■❇▼ ❝❛♥ ❜❡

s❛♠♣❧❡❞ ❜② r✉♥♥✐♥❣ ❝♦♠♣✉t❡r s✐♠✉❧❛t✐♦♥s ❛♥❞✴♦r ✑♠♦❞❡❧❡❞✑ ✭✐♥ t❤❡ s❡♥s ♦❢ ❛♣♣r♦①✐✲

♠❛t❡❞✮ ✉s✐♥❣ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s✳ ●r✐♠♠ ❛♥❞ ❘❛✐❧s❜❛❝❦ ❬●r✐♠♠ ✷✵✵✻❪

♥♦t✐❝❡❞ t❤❛t t❤❡ ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ■❇▼ ❞②♥❛♠✐❝ ✉s✐♥❣ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧

♠♦❞❡❧s ❛tt❡♠♣ts t♦ ❜r✐❞❣❡ t❤❡ ♣❡r❝❡✐✈❡❞ ❣❛♣ ❜❡t✇❡❡♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ❛♥❞ ❝❧❛ss✐❝❛❧

❛♣♣r♦❛❝❤❡s t♦ ❡❝♦❧♦❣✐❝❛❧ ♠♦❞❡❧✐♥❣ ❛♥❞ ❡①♣❛♥❞s t❤❡ ❡❝♦❧♦❣✐sts✬ t♦♦❧❜♦① ❜② ❞❡r✐✈✲

✐♥❣ ♥❡✇ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ✐♥ ✇❤✐❝❤ ✐♥❞✐✈✐❞✉❛❧✲❧❡✈❡❧ ✐♥t❡r❛❝t✐♦♥ ❛r❡

❛❝❦♥♦✇❧❡❞❣❡❞✳

Page 19: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✻ ❈❤❛♣t❡r ✶✳ ■♥tr♦❞✉❝t✐♦♥

✶✳✺✳✶ ❆♣♣r♦①✐♠❛t✐♥❣ s♣❛t✐❛❧❧② ❡①♣❧✐❝✐t ■❇▼s ✇✐t❤ ♠♦♠❡♥t ♠❡t❤✲♦❞s

❲❡ ❢♦❝✉s ♦♥ ❛♣♣r♦①✐♠❛t✐♥❣ s♣❛t✐❛❧❧② ❡①♣❧✐❝✐t ♠✐❝r♦❜✐❛❧ ■❇▼ ✉s✐♥❣ ♠♦♠❡♥ts ❛♣✲

♣r♦①✐♠❛t✐♦♥✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ❤❛s s❤♦✇♥ ♣r♦♠✐s❡ ✐♥ ❞❡r✐✈✐♥❣ ❞❡t❡r♠✐♥✐st✐❝

❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s t❤❛t ❧✐♥❦s ✐♥❞✐✈✐❞✉❛❧✲tr❛✐ts ❛♥❞ ❧♦❝❛❧ ✐♥t❡r❛❝t✐♦♥s

t♦ t❤❡ ♣♦♣✉❧❛t✐♦♥ ❧❡✈❡❧ ❞②♥❛♠✐❝ ❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪❬▼✉rr❡❧❧ ✷✵✵✵❪ ❬❇♦❧❦❡r ✶✾✾✼❪✳ ❚❤❡

❛♣♣r♦❛❝❤ ♣r♦✈✐❞❡s ❛ ❣❡♥❡r❛❧ ❢r❛♠❡✇♦r❦ ❢♦r ❜✉✐❧❞✐♥❣ ❞✐r❡❝t ❞❡t❡r♠✐♥✐st✐❝ ❛♣♣r♦①✐♠❛✲

t✐♦♥s ♦❢ t❤❡ ❞②♥❛♠✐❝ ♦❢ st♦❝❤❛st✐❝ ■❇▼s ✐❢ t❤❡ ❧❛tt❡r ❛r❡ ❛❞❡q✉❛t❡❧② s✐♠♣❧✐✜❡❞✳ ❚❤❡r❡

❛r❡ ✐♥ t❤❡ ❧✐t❡r❛t✉r❡ s❡✈❡r❛❧ ❣♦♦❞ ❡①❛♠♣❧❡s ❞❡♠♦♥str❛t✐♥❣ t❤❛t ♠♦♠❡♥t ♠♦❞❡❧s ❝❛♥

❛❝❝✉r❛t❡❧② ❛♣♣r♦①✐♠❛t❡ t❤❡ ❞②♥❛♠✐❝ ♦❢ ♠❛♥② st♦❝❤❛st✐❝ ■❇▼s ✇✐t❤ t❤❡ ❛❞✈❛♥t❛❣❡s

♦❢ ❜❡✐♥❣ ❞❡t❡r♠✐♥✐st✐❝✱ ❡✈♦❧✈❡ ✐♥ ❛ tr❛❝t❛❜❧❡ st❛t❡ ♣❛r❛♠❡t❡r s♣❛❝❡ ❛♥❞ ❛r❡ ❝♦♠♣✉✲

t❛t✐♦♥❛❧❧② ❧❡ss ❡①♣❡♥s✐✈❡ t❤❛♥ ■❇▼s✳ ❖♥❡ ♦❢ t❤❡ ❛✐♠s ♦❢ t❤✐s t❤❡s✐s ✐s t♦ ✐♥✈❡st✐❣❛t❡

✇❤❡t❤❡r t❤✐s ❛♣♣r♦❛❝❤ ❝❛♥ ❛❧s♦ ❛♣♣❧② t♦ s♣❛t✐❛❧❧② ❡①♣❧✐❝✐t ■❇▼s ✉s❡❞ ✐♥ ♠✐❝r♦❜✐♦❧♦❣②

❛♥❞ ❛ss❡ss t❤❡ ♣♦t❡♥t✐❛❧ ❛♥❞ ❧✐♠✐ts ♦❢ t❤❡ ♠♦♠❡♥t ❛♣♣r♦❛❝❤ ✐♥ ❝❛♣t✉r✐♥❣ t❤❡ ♠❛✐♥

❢❡❛t✉r❡s ♦❢ t❤❡ ■❇▼ s✐♠✉❧❛t❡❞ ♠✐❝r♦❜✐❛❧ s♣❛t✐❛❧ ♣❛tt❡r♥s✳

❚❤❡ ❡ss❡♥❝❡ ♦❢ t❤❡ ♠♦♠❡♥t ❛♣♣r♦❛❝❤ ✐s ✐♥ ❞❡r✐✈✐♥❣ t❤❡ ❞②♥❛♠✐❝s ♦❢ s♣❛t✐❛❧ ♠♦✲

♠❡♥ts ❜② ❝♦♥s✐❞❡r✐♥❣ t❤❡ ♣r♦❝❡ss❡s ❛✛❡❝t✐♥❣ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥s ❛♥❞ ❞❡✜♥❡❞ ❛t t❤❡

❧❡✈❡❧ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡② ♣r♦✈✐❞❡ ❛♥ ❛❧t❡r♥❛t✐✈❡ ✭♦r ❡①t❡♥s✐♦♥✮ t♦ t❤❡ ♠❡❛♥✲✜❡❧❞

❛♣♣r♦❛❝❤ ❛s ♠♦♠❡♥t ♠❡t❤♦❞s ❡❧❡❣❛♥t❧② ❢♦r♠❛❧✐③❡s t❤❡ ♥♦t✐♦♥ ♦❢ t❤❡ ✑✐♥❞✐✈✐❞✉❛❧✬s✲

❡②❡ ✈✐❡✇✑ ♦❢ t❤❡ s♣❛t✐❛❧ ❤❡t❡r♦❣❡♥❡✐t②✳ ❈♦♥s✐❞❡r ❛ ♣♦♣✉❧❛t✐♦♥ ♦❢ N ✐♥❞✐✈✐❞✉❛❧s ❡❛❝❤

❝❤❛r❛❝t❡r✐③❡❞ ✇✐t❤ ❛ s♣❛t✐❛❧ ❧♦❝❛t✐♦♥ x ✐♥ t❤❡ s♣❛❝❡✳ ❚❤❡ ✈❡❝t♦r (xi)i=1..N ❞❡✜♥❡s

t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ♦❢ t❤❡ ♣♦♣✉❧❛t✐♦♥✳ ■❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛r❡ ♥♦t ❧♦❝❛t❡❞ ❛t r❛♥❞♦♠

✐♥ t❤❡ ❞♦♠❛✐♥✱ ✇❡ r❡❢❡r t♦ t❤❡ ♣♦♣✉❧❛t✐♦♥ ❛s ❤❛✈✐♥❣ ❛ s♣❛t✐❛❧ str✉❝t✉r❡✳ ❚❤❡ s♣❛t✐❛❧

♣❛tt❡r♥ ❝❤❛♥❣❡ t❤r♦✉❣❤ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❧❡✈❡❧ st♦❝❤❛st✐❝ ❡✈❡♥ts ✭❜✐rt❤✱ ❞❡❛t❤✱ ♠♦✈❡✲

♠❡♥t✱ ✳✳✮ ❛♥❞ ❛♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ s✐♠✉❧❛t✐♦♥ ❜❛s✐❝❛❧❧② ♣r♦✈✐❞❡s ❛ r❡❛❧✐③❛t✐♦♥

♦❢ t❤✐s ♣❛tt❡r♥✱ ✇❤❡r❡❛s s♣❛t✐❛❧ ♠♦♠❡♥ts ♣r♦✈✐❞❡ ❛ st❛t✐st✐❝❛❧ ❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡

s♣❛t✐❛❧ ♣❛tt❡r♥ ❛♥❞ ♠♦♠❡♥t ♠♦❞❡❧s ❛♣♣r♦①✐♠❛t❡ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡s❡ st❛t✐st✐❝❛❧

q✉❛♥t✐t✐❡s ✐♥ t✐♠❡ ❜② ❝♦♥s✐❞❡r✐♥❣ t❤❡ ❡✛❡❝t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❧❡✈❡❧ ❡✈❡♥ts✳

❙♣❛t✐❛❧ ♠♦♠❡♥ts ❛r❡ ✉s✉❛❧❧② ❡①♣r❡ss❡❞ ✐♥ t❡r♠ ❝♦rr❡❧❛t✐♦♥ ❞❡♥s✐t✐❡s ❢✉♥❝t✐♦♥s✳

❚❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❢♦r♠❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❝❛♥ ❜❡ ❞❡✜♥❡❞ ❜② t❤❡ ❧✐st ♦❢ t❤❡

❧♦❝❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ♦r ✐♥ ❛ ❝♦♥t✐♥✉♦✉s ❢♦r♠✉❧❛t✐♦♥ ✉s✐♥❣ t❤❡ ❞❡♥s✐t② ❢✉♥❝t✐♦♥

p(x) t❤❛t ✐s ♣❡❛❦❡❞ ❛t ❛❧❧ ❧♦❝❛t✐♦♥s ♦❝❝✉♣✐❡❞ ❜② ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ ✐s ③❡r♦ ❡❧s❡✇❤❡r❡✳

❋♦r ❛ ❣✐✈❡♥ s♣❛t✐❛❧ ♣❛tt❡r♥ p t❤❡ ✜rst s♣❛t✐❛❧ ♠♦♠❡♥t ✐s ❞❡✜♥❡❞ ❛s✿

N(p) =1

A

p(x)dx ✭✶✳✷✮

✇❤❡r❡ A ✐s t❤❡ ❛r❡❛ ♦❢ t❤❡ ❝♦♥s✐❞❡r❡❞ ❞♦♠❛✐♥✳ ❚❤✐s ❝♦rr❡s♣♦♥❞s t♦ t❤❡ ♠❡❛♥

❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐♥ t❤❡ s②st❡♠✳ ❚❤❡ s❡❝♦♥❞ ♠♦♠❡♥t ❝♦rr❡s♣♦♥❞s t♦ t❤❡ ❞❡♥s✐t②

♦❢ ♣❛✐rs ❢♦r♠❡❞ ❜② ✐♥❞✐✈✐❞✉❛❧s t❤❛t ❛r❡ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ ❛♣❛rt ❛♥❞ ✐s ❞❡✜♥❡❞ ❛s✿

C(ξ, p) =1

A

p(x)p(x+ ξ)dx ✭✶✳✸✮

Page 20: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✳✻✳ ▼❡t❤♦❞s ❛♥❞ t♦♦❧s ✼

❚❤❡ t❤✐r❞ ♠♦♠❡♥t✱ ❞❡♥♦t❡❞ T (ξ, ξ′, p) ❝♦rr❡s♣♦♥❞s t♦ t❤❡ ❞❡♥s✐t② ♦❢ tr✐♣❧❡t ♦❢

✐♥❞✐✈✐❞✉❛❧s ✇❤❡r❡ t❤❡ ✜rst ♣❛✐r ✐♥ t❤❡ tr✐♣❧❡t ✐s s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡

ξ ❛♥❞ t❤❡ s❡❝♦♥❞ ♣❛✐r ✇✐t❤ ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ′✳ ❲❡ ❝❛♥ ❛❧s♦ ❞❡✜♥❡ ❛❞❞✐t✐♦♥❛❧

❤✐❣❤❡r ♦r❞❡r s♣❛t✐❛❧ ♠♦♠❡♥t✱ ❜✉t ✉s✉❛❧❧② t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ✐s r❡str✐❝t❡❞

t♦ t❤❡ t❤❡s❡ t❤r❡❡ s♣❛t✐❛❧ ♠♦♠❡♥ts✳

❚❤❡ ❞❡r✐✈❛t✐♦♥ ♦❢ ❛ tr❛❝t❛❜❧❡ ❞❡t❡r♠✐♥✐st✐❝ ♠♦♠❡♥t ♠♦❞❡❧ ❢r♦♠ t❤❡ st♦❝❤❛st✐❝

r✉❧❡s ♦❢ t❤❡ ■❇▼ r❡q✉✐r❡s s♦♠❡ ❧❡✈❡❧ ♦❢ ❛♣♣r♦①✐♠❛t✐♦♥ ✇❤✐❝❤ ❛r❡ ✈❡r✐✜❡❞ ❜② ❝♦♥✲

❢r♦♥t✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ t♦ t❤❡ ■❇▼ s✐♠✉❧❛t✐♦♥s✳ ❚❤❡ ♠❛✐♥ ❛♣♣r♦①✐♠❛t✐♦♥

♥❡❡❞❡❞ ❢♦r ✐♥ ❞❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✐s r❡❧❛t❡❞ t♦ t❤❡ ❝❛s❝❛❞❡ ♦❢ ❤✐❡r❛r❝❤②

♦❢ s♣❛t✐❛❧ ♠♦♠❡♥t ✇❤✐❝❤ ❛t s♦♠❡ ❧❡✈❡❧ ♥❡❡❞ t♦ ❜❡ ❝✉t ♦✛ ✉s✐♥❣ ❛ ❝❧♦s✉r❡ ❡q✉❛✲

t✐♦♥✳ ❖❢t❡♥ ♠♦♠❡♥t ♠♦❞❡❧s ❛r❡ ❧✐♠✐t❡❞ t♦ t❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥ts

❛♥❞ ♥❡❣❧❡❝t t❤❡ tr✐♣❧❡ ❝♦rr❡❧❛t✐♦♥ ❜❡t✇❡❡♥ t❤❡ ♣♦s✐t✐♦♥s ♦❢ t❤r❡❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡

✉♥❞❡r❧②✐♥❣ ❛ss✉♠♣t✐♦♥ ✐s t❤❛t t❤❡ ♣r♦❜❛❜✐❧✐t② ♦❢ ❡♥❝♦✉♥t❡r✐♥❣ ❛ ♣❛rt✐❝✉❧❛r tr✐♣❧❡t

❝♦♥✜❣✉r❛t✐♦♥ ✐s ❢✉❧❧② ❣✐✈❡♥ ❜② ♣❛✐r ❞❡♥s✐t✐❡s ❬❱❛♥ ❇❛❛❧❡♥ ✷✵✵✵❪✳ ❆♥♦t❤❡r ✐♠♣♦rt❛♥t

❛♣♣r♦①✐♠❛t✐♦♥ ✐s t❤❛t t❤❡ ♠♦♠❡♥t ❡q✉❛t✐♦♥ ❛r❡ ❜❛s❡❞ ♦♥ t❤❡ ❛✈❡r❛❣❡ ♥❡✐❣❤❜♦r❤♦♦❞

❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❍❡♥❝❡ ✢✉❝t✉❛t✐♦♥s ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧s

❛r❡ ♥♦t ❝♦♥s✐❞❡r❡❞ ✐♥ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧s✳

✶✳✻ ▼❡t❤♦❞s ❛♥❞ t♦♦❧s

✶✳✻✳✶ ■❇▼ ❞❡s❝r✐♣t✐♦♥

■❇▼ ❞❡s❝r✐♣t✐♦♥ ✐s ♦❢t❡♥ ❛ ❝r✐t✐❝❛❧ st❡♣✳ ❲❤✐❧❡ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❛r❡ ❢✉❧❧②

❞❡s❝r✐❜❡❞ ✇✐t❤ ❛ s❡t ♦❢ ❡q✉❛t✐♦♥s✱ ✈❛r✐❛❜❧❡ ❞❡✜♥✐t✐♦♥s ❛♥❞ ❛ ♣❛r❛♠❡t❡r t❛❜❧❡✱ t❤❡

❞❡s❝r✐♣t✐♦♥ ♦❢ ❛♥ ■❇▼ ✉s✉❛❧❧② r❡q✉✐r❡s ❛ ❝♦♠❜✐♥❛t✐♦♥ ♦❢ ♠❛t❤❡♠❛t✐❝❛❧ ❡q✉❛t✐♦♥s✱

❛❧❣♦r✐t❤♠✐❝ r✉❧❡s ✭✐❢ ✳✳ t❤❡♥✮ ❛♥❞ ❧❡♥❣t❤② ✈❡r❜❛❧ ❞❡s❝r✐♣t✐♦♥✳ ❚❤✐s ♦❢t❡♥ ♠❛❦❡s t❤❡

r❡♣r♦❞✉❝t✐♦♥ ♦❢ ❛♥ ■❇▼ ❞✐✣❝✉❧t ❜❡❝❛✉s❡ ♦❢ t❤❡ ❛♠❜✐❣✉✐t② t❤❛t ♠❛② ❛r✐s❡ ✐♥ t❤❡

❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ ♠♦❞❡❧✳ ❘❡❝❡♥t❧② ❛ st❛♥❞❛r❞ ♣r♦t♦❝♦❧ ❢♦r ❞❡s❝r✐❜✐♥❣ ■❇▼s ❝❛❧❧❡❞

❖❉❉ ✭❖✈❡r✈✐❡✇✱ ❉❡s✐❣♥ ❝♦♥❝❡♣ts ❛♥❞ ❉❡t❛✐❧s✮ ❤❛s ❜❡❡♥ ♣r♦♣♦s❡❞ ❬●r✐♠♠ ✷✵✵✻❪✳

❚❤❡ ♣r♦t♦❝♦❧ ❛✐♠s t♦ str✉❝t✉r❡ t❤❡ ✐♥❢♦r♠❛t✐♦♥ ❛❜♦✉t t❤❡ ■❇▼ ✐♥ ❛ st❛♥❞❛r❞ s❡✲

q✉❡♥❝❡ ✭✜❣✉r❡ ✺✳✶✮✳ ❚❤❡ ❧♦❣✐❝ ❜❡❤✐♥❞ ❖❉❉ ✐s t♦ ♣r♦✈✐❞❡ ✜rst t❤❡ ❝♦♥t❡①t ❛♥❞

❣❡♥❡r❛❧ ✐♥❢♦r♠❛t✐♦♥ ✭❖✈❡r✈✐❡✇✮✱ ❢♦❧❧♦✇❡❞ ❜② ♠♦r❡ str❛t❡❣✐❝ ❝♦♥s✐❞❡r❛t✐♦♥s ✭❉❡s✐❣♥

❝♦♥❝❡♣ts✮ ❛♥❞ ✜♥❛❧❧② ♠♦r❡ t❡❝❤♥✐❝❛❧ ❞❡t❛✐❧s ❬●r✐♠♠ ✷✵✵✻❪✳ ■♥ t❤✐s t❤❡s✐s ✇❡ ❛❞♦♣t

t❤❡ ❖❉❉ ❢r❛♠❡✇♦r❦ t♦ ❞❡s❝r✐❜❡ t❤❡ ■❇▼s✳

✶✳✻✳✷ ■❇▼ ✐♠♣❧❡♠❡♥t❛t✐♦♥

❚❤❡r❡ ❛r❡ s❡✈❡r❛❧ ✢❡①✐❜❧❡ ♠♦❞❡❧✐♥❣ ❡♥✈✐r♦♥♠❡♥ts ❢♦r ✐♠♣❧❡♠❡♥t✐♥❣ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧s✳ ❙✉❝❤ ❡♥✈✐r♦♥♠❡♥ts ✐♥❝❧✉❞❡ s❡✈❡r❛❧ ✉t✐❧✐t✐❡s ❢♦r st♦r✐♥❣ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✱ ♣❡r✲

❢♦r♠✐♥❣ ♥❡✐❣❤❜♦r s❡❛r❝❤✱ ❝r❡❛t✐♥❣ ❛ ❣r❛♣❤✐❝❛❧ ✉s❡r ✐♥t❡r❢❛❝❡✱ ❛♥❛❧②③✐♥❣ t❤❡ s✐♠✉❧❛t✐♦♥

❛♥❞ tr❛❝❦✐♥❣ t❤❡ st❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❆❣❡♥t✲❜❛s❡❞ ♠♦❞❡❧✐♥❣ ❡♥✈✐r♦♥♠❡♥t ♦❢ t❤✐s

❦✐♥❞ ✐♥❝❧✉❞❡ ◆❡t▲♦❣♦✱ ❘❡♣❛st ❛♥❞ ▼❛s♦♥✳ ■♥ t❤✐s ✇♦r❦ ✇❡ ✉s❡❞ ▼❛s♦♥ ❧✐❜r❛r②✱ ❛♥

Page 21: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✽ ❈❤❛♣t❡r ✶✳ ■♥tr♦❞✉❝t✐♦♥

❋✐❣✉r❡ ✶✳✶✿ ❚❤❡ s❡✈❡♥ ❡❧❡♠❡♥ts ♦❢ t❤❡ ❖❉❉ ♣r♦t♦❝♦❧ ❢♦r t❤❡ ❞❡s❝r✐♣t✐♦♥ ♦❢ ✐♥❞✐✈✐❞✉❛❧✲

❜❛s❡❞ ♠♦❞❡❧s✳ ❚❤❡ ❡❧❡♠❡♥ts ❛r❡ ❣r♦✉♣❡❞ ✐♥t♦ t❤❡ t❤r❡❡ ❜❧♦❝❦s✿ ❖✈❡r✈✐❡✇✱ ❉❡s✐❣♥

❝♦♥❝❡♣ts✱ ❛♥❞ ❉❡t❛✐❧s ✭r❡♣r♦❞✉❝❡❞ ❢r♦♠ ❬●r✐♠♠ ✷✵✵✻❪✮

♦♣❡♥ s♦✉r❝❡ ❥❛✈❛✲❜❛s❡❞ ❡✈❡♥t✲❞r✐✈❡♥ ❧✐❜r❛r② ❢♦r ✐♠♣❧❡♠❡♥t✐♥❣ ❛❣❡♥t✲❜❛s❡❞ ♠♦❞❡❧s

❬▲✉❦❡ ✷✵✵✹❪✳

✶✳✻✳✸ ❊①♣❧♦r✐♥❣ t❤❡ ■❇▼s ✉s✐♥❣ ❙✐♠❊①♣❧♦r❡r

❲❡ ✉s❡ ❙✐♠❊①♣❧♦r❡r t♦ ♠❛♥❛❣❡ ♥✉♠❡r✐❝❛❧ ■❇▼ ❡①♣❡r✐♠❡♥t❛t✐♦♥s✳ ❙✐♠❊①✲

♣❧♦r❡r ✐s ❛ ❢r❛♠❡✇♦r❦ ❞❡s✐❣♥❡❞ ❢♦r ♠❛♥❛❣✐♥❣ s✐♠✉❧❛t✐♦♥ ❡①♣❡r✐♠❡♥ts ✭s❡❡✿

✇✇✇✳s✐♠❡①♣❧♦r❡r✳♦r❣✮✳

✶✳✼ ❘❡♣♦rt ♦✉t❧✐♥❡

❚❤❡ r❡♣♦rt ✐s ♦r❣❛♥✐③❡❞ ✐♥ s✐① ❝❤❛♣t❡rs ✭✷✲✼✮ ✇✐t❤ ❛♥ ✐♥tr♦❞✉❝t♦r② ❝❤❛♣t❡r ✭❝❤❛♣t❡r

✶✮ ❛♥❞ ❛ ❝♦♥❝❧✉❞✐♥❣ ❝❤❛♣t❡r ✭❝❤❛♣t❡r ✽✮✳ ■♥ ❝❤❛♣t❡r ✷✲✹ ✇❡ ❢♦❝✉s ♦♥ ❛ s✐♠♣❧❡

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✇❤✐❧❡ ✐♥ ❝❤❛♣t❡rs ✺✲✼ ✇❡ ✐♥✈❡st✐❣❛t❡

t❤❡ ❡✛❡❝t ♦❢ ❛❞❞✐♥❣ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② ♦♥ t❤❡ ♦❜s❡r✈❡❞ ♣❛tt❡r♥s✳ ❖✉r ♠❡t❤♦❞♦❧♦❣✐❝❛❧

str❛t❡❣② ❝♦♥s✐sts ✐♥ st❛rt✐♥❣ ✇✐t❤ ❛ ❞❡t❛✐❧❡❞ ■❇▼ t❤❛t ♠✐♠✐❝s t❤❡ ♦❜s❡r✈❡❞ ❜❡❤❛✈✐♦r

♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✱ t❤❡♥ s✐♠♣❧✐❢② ✐t t♦ ❞❡r✐✈❡ t♦ ❛ ❧❡✈❡❧ t❤❛t ❛❧❧♦✇s t❤❡ ❞❡r✐✈❛t✐♦♥

♦❢ ❛♥ ❛♣♣r♦①✐♠❛t✐♥❣ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s✳ ❲❡ ❢♦❝✉s ♠❛✐♥❧② ♦♥ t❤❡

❞❡r✐✈❛t✐♦♥ ♦❢ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧s t❤❛t ❝❛♣t✉r❡ t❤❡ ♠❛✐♥ ❢❡❛t✉r❡s ♦❢ t❤❡

s♣❛t✐❛❧ ♣❛tt❡r♥ ❞②♥❛♠✐❝✳ ◆❡✈❡rt❤❡❧❡ss✱ ✇❡ ♣r♦✈✐❞❡ ❛ ❝♦♠♣❛r✐s♦♥ t♦ ❛ ❞✐✛✉s✐♦♥✲

r❡❛❝t✐♦♥ ♠♦❞❡❧s ✐♥ ❝❤❛♣t❡r ✷✳

• ■♥ ❝❤❛♣t❡r ✷ ✇❡ ❝♦♠♣❛r❡ ❛ s✐♠♣❧❡ s♣❛t✐❛❧❧②✲❡①♣❧✐❝✐t ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ✭■❇▼✮

❢♦r ❜❛❝t❡r✐❛ ❝♦❧♦♥② ❣r♦✇t❤ ✐♥✈♦❧✈✐♥❣ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✇✐t❤ ❛♥ ❡q✉✐✈❛❧❡♥t

❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧✳ ❇♦t❤ ♠♦❞❡❧ ❛r❡ ❡①tr❛❝t❡❞ ❢r♦♠ t❤❡ ❧✐t❡r❛t✉r❡

❬❑r❡❢t ✶✾✾✽❪ ❢♦r t❤❡ ■❇▼ ❛♥❞ ❬❊❜❡r❧ ✷✵✵✶❪ ❢♦r t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧✳

❖✉r ❛✐♠ ❜❡❤✐♥❞ t❤✐s ❝♦♠♣❛r✐s♦♥ ✐s t♦ ✐❧❧✉str❛t❡ t❤❡ ♣♦t❡♥t✐❛❧ ❛♥❞ ❧✐♠✐t ♦❢ ❡❛❝❤

❛♣♣r♦❛❝❤✳

Page 22: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✳✼✳ ❘❡♣♦rt ♦✉t❧✐♥❡ ✾

• ■♥ ❝❤❛♣t❡r ✸ ✇❡ s✐♠♣❧✐❢② t❤❡ ❝♦❧♦♥② ❣r♦✇t❤ ■❇▼ ❛♥❞ ❛♣♣r♦①✐♠❛t❡ t❤❡ s✐♠♣❧✐✜❡❞

■❇▼ ✇✐t❤ ❛♥ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦♠❡♥t ♠♦❞❡❧✳

• ■♥ ❝❤❛♣t❡r ✹ ✇❡ ✐♥✈❡st✐❣❛t❡ t❤❡ st❛t✐♦♥❛r② ♣❛tt❡r♥s t❤❛t ❛r✐s❡ ✐♥ ❛ s②st❡♠

✇✐t❤ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛ ❛♥❞ ❝♦♠♣❛r❡ t❤❡s❡ ♣❛tt❡r♥s t♦ t❤♦s❡ ②✐❡❧❞❡❞ ❜② ❛♥

❛♣♣r♦①✐♠❛t✐♥❣ ♠♦♠❡♥t ♠♦❞❡❧✳

• ■♥ ❝❤❛♣t❡r ✺ t♦ ✼ ✇❡ ❢♦❝✉s ♦♥ ❛ ♥❡✇ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ t❤❛t ✐♥❝❧✉❞❡s ❜❛❝✲

t❡r✐❛ s✉r❢❛❝❡✲❛ss♦❝✐❛t❡❞ ♠♦t✐❧✐t②✳ ❚❤❡ ♦r✐❣✐♥❛❧✐t② ♦❢ t❤✐s ♠♦❞❡❧ ✐s ✐♥ ❛ss✉♠✐♥❣

t❤❛t t❤❡ ❡①❝r❡t✐♦♥ ♦❢ ❡①♦♣♦❧②♠❡r✐❝ s✉❜st❛♥❝❡s ❜② t❤❡ ❜❛❝t❡r✐❛ t❡♥❞ t♦ r❡❞✉❝❡s

t❤❡✐r ♠✐❣r❛t✐♦♥ ❝❛♣❛❝✐t② ②✐❡❧❞✐♥❣ ❛ r✐❝❤ ✈❛r✐❡t② ♦❢ s♣❛t✐❛❧ ♣❛tt❡r♥s✳ ■♥ ❝❤❛♣t❡r

✺ ✇❡ ♣r❡s❡♥t t❤❡ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

• ■♥ ❝❤❛♣t❡r ✻ ✇❡ ♣r♦✈✐❞❡ ❛ ✜rst s✐♠♣❧✐✜❝❛t✐♦♥ ♦❢ t❤❡ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧ ✐♥ ✇❤✐❝❤ ✇❡ ❦❡❡♣ t❤❡ ❡①♦♣♦❧②♠❡r✐❝ s✉❜st❛♥❝❡ ❞②♥❛♠✐❝ ❛♥❞ ❛♣♣r♦①✐♠❛t❡

t❤❡ s✐♠♣❧✐✜❡❞ ♠♦❞❡❧ ✉s✐♥❣ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ t❡❝❤♥✐q✉❡s

• ■♥ ❝❤❛♣t❡r ✼ ✇❡ ♣r♦✈✐❞❡ ❛ ❢✉rt❤❡r s✐♠♣❧✐✜❝❛t✐♦♥ ♦❢ t❤❡ ♠♦❞❡❧ t❤❛t st✐❧❧ ❛❧❧♦✇

t♦ r❡♣r♦❞✉❝❡ t❤❡ ♠❛✐♥ ♣❛tt❡r♥s ♦❜s❡r✈❡❞ ✐♥ t❤❡ ♣r❡✈✐♦✉s ♠♦❞❡❧s✳ ❲❡ ❝♦♠♣❛r❡

t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ r❡s✉❧ts t♦ t❤♦s❡ ♦❜t❛✐♥ ✇✐t❤ ❛♥ ❛♣♣r♦①✐♠❛t✐♥❣ ♠♦♠❡♥t

♠♦❞❡❧✳

• ❋✐♥❛❧❧②✱ ✐♥ ❝❤❛♣t❡r ✽ ✇❡ s✉♠♠❛r✐③❡ t❤❡ ♠❛✐♥ r❡s✉❧ts ❛♥❞ ♣r♦♣♦s❡ s♦♠❡ ♣❡r✲

s♣❡❝t✐✈❡s✳

Page 23: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and
Page 24: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❈❤❛♣t❡r ✷

▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿

❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥

♠♦❞❡❧

❈♦♥t❡♥ts

✷✳✶ ▼♦❞❡❧✐♥❣ ♠✐❝r♦❜✐❛❧ s♣❛t✐❛❧ ♣❛tt❡r♥s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✷

✷✳✷ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸

✷✳✸ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✹

✷✳✸✳✶ ❖✈❡r✈✐❡✇ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✹

✷✳✸✳✷ ❉❡s✐❣♥ ❈♦♥❝❡♣ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✺

✷✳✸✳✸ ❉❡t❛✐❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✺

✷✳✸✳✹ ▼♦❞❡❧ ♣❛r❛♠❡t❡rs ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼

✷✳✹ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ s✐♠✉❧❛t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✼

✷✳✺ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✽

✷✳✻ ❈♦♠♣❛r✐♥❣ t❤❡ ■❇▼ ✇✐t❤ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ✳ ✳ ✳ ✷✷

✷✳✼ ❉✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✷✸

❉✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧s ✭❉❘▼✮ ❛r❡ tr❛❞✐t✐♦♥❛❧❧② ✉s❡❞ ❢♦r s✐♠✉❧❛t✐♥❣ t❤❡ ❢♦r✲

♠❛t✐♦♥ ♦❢ s♣❛t✐❛❧ ♣❛tt❡r♥s ✐♥ ❜✐♦❧♦❣✐❝❛❧ s②st❡♠s ❬▼✉rr❛② ✷✵✵✶❪✳ ❆ ✈❛st ♠❛t❤❡✲

♠❛t✐❝❛❧ t❤❡♦r② ❢♦r ❉❘▼s ❛♥❞ ❛ ❝♦♥s✐❞❡r❛❜❧❡ ❜♦❞② ♦❢ ❧✐t❡r❛t✉r❡ ♦❢ t❤❡✐r ❛♣♣❧✐❝❛✲

t✐♦♥s ✐♥ ❜✐♦❧♦❣② ❛♥❞ ♠✐❝r♦❜✐❛❧ s②st❡♠s ♥♦✇ ❡①✐st✳ ■♥ t❤✐s ❝❤❛♣t❡r ✇❡ ❝♦♠♣❛r❡ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✭■❇▼✮ ❛❞❛♣t❡❞ ❢r♦♠ ❬❑r❡❢t ✶✾✾✽❪ ❛♥❞ ❛ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥

♠♦❞❡❧ ❞❡s❝r✐❜❡❞ ✐♥ ❬❊❜❡r❧ ✷✵✵✶❪✳ ❇♦t❤ ♠♦❞❡❧s r❡♣r❡s❡♥t t❤❡ ❝♦r❡ ♦❢ s❡✈❡r❛❧ ♠♦r❡

❝♦♠♣❧❡① ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ♠♦❞❡❧s ✐♥✈♦❧✈✐♥❣ ♠✉❧t✐♣❧❡ ♠✐❝r♦❜✐❛❧ ❣r♦✉♣s ❛♥❞ ♠❡t❛❜♦✲

❧✐t❡s ❬❑r❡❢t ✷✵✵✶❪❬❊❜❡r❧ ✷✵✵✶❪❬P✐❝✐♦r❡❛♥✉ ✷✵✵✹❪❬❳❛✈✐❡r ✷✵✵✺❪✳ ❲❡ ✉s❡ ❜♦t❤ ♠♦❞❡❧s t♦

s✐♠✉❧❛t❡ t❤❡ ❣r♦✇t❤ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ❝♦❧♦♥② ✐♥✐t✐❛t❡❞ ✇✐t❤ ❛ s✐♥❣❧❡ ❝❡❧❧ ❧♦❝❛t❡❞ ❛t t❤❡

❝❡♥t❡r ♦❢ ❛ sq✉❛r❡❞ t✇♦✲❞✐♠❡♥s✐♦♥❛❧ ❞♦♠❛✐♥✳ ❚❤❡ ❝❡❧❧ ❣r♦✇s ❜② ✉♣t❛❦✐♥❣ ❛ ❞✐✛✉s✐✈❡

♥✉tr✐❡♥t ✇❤✐❝❤ ❝♦♥❝❡♥tr❛t✐♦♥ ✐s ✐♠♣♦s❡❞ ❛t t❤❡ ❞♦♠❛✐♥ ❜♦✉♥❞❛r②✳ ❲❡ ♣r♦♣♦s❡ t♦

❝♦♠♣❛r❡ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥s ♦❢ t❤❡ s✐♠✉❧❛t❡❞ ❝♦❧♦♥✐❡s ②✐❡❧❞❡❞ ❜② ❜♦t❤ ♠♦❞❡❧s ✐♥

t✇♦ ❞✐✛❡r❡♥t ❣r♦✇t❤ r❡❣✐♠❡s✿ t❤❡ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡ ✇❤❡r❡ t❤❡ ❣r♦✇t❤ ♦❢ t❤❡

Page 25: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✷

❈❤❛♣t❡r ✷✳ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

❜❛❝t❡r✐❛ ✐s ❧✐♠✐t❡❞ ❜② t❤❡✐r ♥✉tr✐♠❡♥t ✉♣t❛❦❡ ❝❛♣❛❝✐t② ❛♥❞ t❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬

r❡❣✐♠❡ ✐♥ ✇❤✐❝❤ t❤❡ ❜❛❝t❡r✐❛ ❣r♦✇t❤ ✐s ❧✐♠✐t❡❞ ❜② t❤❡ ♥✉tr✐❡♥t tr❛♥s♣♦rt✳ ❚❤r♦✉❣❤

t❤✐s ❝♦♠♣❛r✐s♦♥✱ ✇❡ ❛✐♠ t♦ ✐❧❧✉str❛t❡ t❤❡ ♣♦t❡♥t✐❛❧ ❛♥❞ ❧✐♠✐t❛t✐♦♥ ♦❢ ❡❛❝❤ ❛♣♣r♦❛❝❤✳

❚❤❡ ❝❤❛♣t❡r ✐s ♦r❣❛♥✐③❡❞ ✐♥ s✐① s❡❝t✐♦♥s✳ ❚❤❡ ✜rst s❡❝t✐♦♥ ✐♥tr♦❞✉❝❡s t❤❡ ♣r♦❜❧❡♠

♦❢ ♠♦❞❡❧✐♥❣ ♠✐❝r♦❜✐❛❧ s♣❛t✐❛❧ ♣❛tt❡r♥s ✉s✐♥❣ ■❇▼s ❛♥❞ ❉❘▼s✳ ■♥ t❤❡ s❡❝♦♥❞ s❡❝t✐♦♥

✇❡ ♣r❡s❡♥t t❤❡ ■❇▼ ✉s✐♥❣ t❤❡ ❖❉❉ ✭❖✈❡r✈✐❡✇✱ ❉❡s✐❣♥ ❈♦♥❝❡♣ts ❛♥❞ ❉❡t❛✐❧s✮ ♣r♦✲

t♦❝♦❧ r❡❝♦♠♠❡♥❞❡❞ ✐♥ ❬●r✐♠♠ ✷✵✵✻❪✳ ■♥ t❤❡ t❤✐r❞ s❡❝t✐♦♥ ✇❡ s✐♠✉❧❛t❡ t❤❡ ❣r♦✇t❤ ♦❢

❛ ❝♦❧♦♥② ✐♥ t❤❡ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ ❛♥❞ t❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡s✳ ■♥ t❤❡ ❢♦✉rt❤

s❡❝t✐♦♥ ✇❡ ♣r❡s❡♥t t❤❡ ❛❣❣r❡❣❛t❡❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧✳ ■♥ t❤❡ ✜❢t❤ s❡❝t✐♦♥ ✇❡

❝♦♠♣❛r❡ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ♣❛tt❡r♥ t♦ t❤❡ ❛✈❡r❛❣❡ ♣❛tt❡r♥ ②✐❡❧❞❡❞ ❜② t❤❡

■❇▼✳ ❋✐♥❛❧❧② ✇❡ ❞✐s❝✉ss t❤❡ ❧✐♠✐t❛t✐♦♥ ❛♥❞ ♣♦t❡♥t✐❛❧ ♦❢ ❡❛❝❤ ❛♣♣r♦❛❝❤✳

✷✳✶ ▼♦❞❡❧✐♥❣ ♠✐❝r♦❜✐❛❧ s♣❛t✐❛❧ ♣❛tt❡r♥s

❚❤❡ ♣r♦❜❧❡♠ ♦❢ ❛❣❣r❡❣❛t✐♦♥ ♦❢ ♠✐❝r♦❜✐❛❧ ❝❡❧❧s✱ ✐♥ ♣❛rt✐❝✉❧❛r ❜❛❝t❡r✐❛✱ ✐s ❛ ❝❡♥✲

tr❛❧ ♦♥❡ ✐♥ ♠✐❝r♦❜✐❛❧ ❡❝♦❧♦❣②✳ ❉❡♣❡♥❞✐♥❣ ♦♥ t❤❡ ❜❛❝t❡r✐❛❧ s♣❡❝✐❡s ❛♥❞ t❤❡ ❝✉❧t✉r❡

❝♦♥❞✐t✐♦♥s✱ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❝❛♥ ❢♦r♠ ❝♦❧♦♥✐❡s ❬❇❡♥✲❏❛❝♦❜ ✷✵✵✵❪✱ ✢♦❝s ❬❙❝❤♠✐❞ ✷✵✵✸❪✱

❣r❛♥✉❧❡s ❬▼♦r❣❡♥r♦t❤ ✶✾✾✼❪ ❛♥❞ ❜✐♦✜❧♠s ❬❈♦st❡rt♦♥ ✶✾✾✺❪ t❤❛t ❡①❤✐❜✐t ❛ ❣r❡❛t ❞✐✈❡r✲

s✐t② ♦❢ ❢♦r♠s✳ ❙✉❝❤ ♣❛tt❡r♥s ❛r❡ ♦❢t❡♥ ♦❜s❡r✈❛❜❧❡ ❛t t❤❡ ❧❡✈❡❧ ♦❢ t❤❡ ♣♦♣✉❧❛t✐♦♥ ❜✉t

❛r❡ t♦ ❛ ❧❛r❣❡ ❡①t❡♥t ♠❡❞✐❛t❡❞ ❜② t❤❡ ♣r♦❝❡ss❡s t❛❦✐♥❣ ♣❧❛❝❡ ❛t t❤❡ ❧❡✈❡❧ ♦❢ t❤❡ ✐♥❞✐✲

✈✐❞✉❛❧ ❝❡❧❧s✳ ▼✉❝❤ ❡✛♦rt ✐s ❞❡❞✐❝❛t❡❞ t♦ ❡①♣❧♦r❡ t❤❡ ❧✐♥❦❛❣❡ ❜❡t✇❡❡♥ t❤❡s❡ ❧❡✈❡❧s✳ ■♥

♣❛rt✐❝✉❧❛r ❤♦✇ ❝❤❛♥❣❡s ✐♥ ✐♥❞✐✈✐❞✉❛❧s✬ r❡s♣♦♥s❡s t♦ t❤❡✐r ❡♥✈✐r♦♥♠❡♥t tr❛♥s❧❛t❡ ✐♥t♦

❝❤❛♥❣❡s ✐♥ ♦❜s❡r✈❛❜❧❡ ♣❛tt❡r♥s ❛♥❞ ❝♦♥✈❡rs❡❧② ❤♦✇ t❤❡ ❡♠❡r❣❡♥❝❡ ♦❢ t❤❡s❡ s♣❛t✐❛❧

str✉❝t✉r❡s ❛✛❡❝t t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳

■❇▼s ❛♥❞ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ❜❛s❡❞ ♦♥ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ❡q✉❛✲

t✐♦♥ ❢r❛♠❡✇♦r❦ ❤❛✈❡ ❜♦t❤ ❜❡❡♥ ❡①t❡♥s✐✈❡❧② ✉s❡❞ t♦ ✐♥✈❡st✐❣❛t❡ ❤♦✇ t❤❡s❡ s♣❛t✐❛❧

str✉❝t✉r❡s ❢♦r♠ ❛♥❞ ❡✈♦❧✈❡ ✐♥ t✐♠❡ ❬●r✐♠s♦♥ ✶✾✾✹❪ ❬❑r❡❢t ✷✵✵✶❪ ❬P✐❝✐♦r❡❛♥✉ ✷✵✵✹❪

❬▲❛❝❛st❛ ✶✾✾✾❪❬❊❜❡r❧ ✷✵✵✶❪❬❈♦❣❛♥ ✷✵✵✹❪❬❆❧♣❦✈✐st ✷✵✵✼❪✳ ❲❤✐❧❡ ■❇▼s ❛tt❡♠♣t t♦

s✐♠✉❧❛t❡ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢ ♠✐❝r♦❜✐❛❧ ♣❛tt❡r♥s ❜② s♣❡❝✐❢②✐♥❣ t❤❡ ❜❡❤❛✈✐♦r❛❧ ❛♥❞

✐♥t❡r❛❝t✐♦♥s r✉❧❡s ❛t t❤❡ ❧❡✈❡❧ ♦❢ t❤❡ ❞✐s❝r❡t❡ ✐♥❞✐✈✐❞✉❛❧s✱ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧s

r❡♣r❡s❡♥t t❤❡ ♣❛tt❡r♥ ❛s ❛♥ ❡♥t✐t② ✭❛ ❞❡♥s✐t② ✜❡❧❞✮ ❛♥❞ ❛tt❡♠♣t t♦ ❝❛♣t✉r❡ ❤♦✇ t❤✐s

❡♥t✐t② ❡✈♦❧✈❡ ✐♥ t✐♠❡✳ ❚❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ✐s ✉s✉❛❧❧② ❝♦♥s✐❞❡r❡❞ ❛s t❤❡ ❝♦♥✲

t✐♥✉✉♠ ❧✐♠✐t ♦❢ t❤❡ ■❇▼ ✇❤❡♥ t❤❡ ♥✉♠❜❡r ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐s ❧❛r❣❡✳ ❚❤✐s ✐♠♣❧✐❡s

t❤❛t t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ❝❛♥ ❜❡ ❞❡r✐✈❡❞ r✐❣♦r♦✉s❧② ❢r♦♠ t❤❡ r✉❧❡s st❛t❡❞ ✐♥

t❤❡ ■❇▼✳ ❍♦✇❡✈❡r ✐♥ ♣r❛❝t✐❝❡✱ t❤❡ ❞❡r✐✈❛t✐♦♥ ♦❢ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ❡q✉❛t✐♦♥ ❢r♦♠

r✐❣♦r♦✉s ❝♦♥s✐❞❡r❛t✐♦♥s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❧❡✈❡❧ r✉❧❡s ✐s ♦❢t❡♥ ❝♦♠♣❧❡① ❛♥❞ ❢❡❛s✐❜❧❡

♦♥❧② ❢♦r s♦♠❡ ✐❞❡❛❧ s②st❡♠s✳ ❈♦♥s❡q✉❡♥t❧②✱ ❛♥❞ ❛s ✇✐❧❧ ❜❡ ✐❧❧✉str❛t❡❞ ✐♥ t❤✐s ❝❤❛♣t❡r

✭s❡❝t✐♦♥ ✸✮✱ ❛ss✉♠♣t✐♦♥s ❛♥❞ s✐♠♣❧✐✜❝❛t✐♦♥s ❤❛✈❡ t♦ ❜❡ ♠❛❞❡ ✐♥ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢

t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ❛♥❞ ❝♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ t♦ t❤❡

■❇▼ ❝❛♥ ❜❡ ❤❡❧♣❢✉❧ t♦ ♠❡❛s✉r❡ t❤❡ ✐♠♣❛❝t ♦❢ t❤❡s❡ s✐♠♣❧✐✜❝❛t✐♦♥s✳

Page 26: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✷✳✷✳ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✶✸

❑r❡❢t ❡t ❛❧✳ ❬❑r❡❢t ✶✾✾✽❪ ♣r♦♣♦s❡❞ ❛♥ ♦r✐❣✐♥❛❧ ■❇▼ ✭❝❛❧❧❡❞ ❇❛❝s✐♠✮ ✐♥✈♦❧✈✐♥❣

❞✐s❝r❡t❡ r❡♣r❡s❡♥t❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❛♥❞ ❛♥ ❡①♣❧✐❝✐t ❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡✐r

♣r♦❝❡ss❡s ✭❣r♦✇t❤✱ ❞✐✈✐s✐♦♥✱ s❤♦✈✐♥❣✮✳ ❚❤❡ s❤♦✈✐♥❣ ♣r♦❝❡ss✱ ❛ ♠❡❝❤❛♥✐s♠s ❜② ✇❤✐❝❤

t❤❡ ✐♥❞✐✈✐❞✉❛❧s ♣✉s❤ ❡❛❝❤ ♦t❤❡rs t♦ r❡❧❛① ♦✈❡r❧❛♣♣✐♥❣✱ ✐s t❤❡ ♠❛✐♥ ♣r♦❝❡ss r❡s♣♦♥s✐❜❧❡

♦❢ t❤❡ ❝♦❧♦♥② ❡①♣❛♥s✐♦♥✳ ■♥ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ ♣r♦♣♦s❡❞ ✐♥

❬❊❜❡r❧ ✷✵✵✶❪ t❤❡ ❜❛❝t❡r✐❛ s♣❛t✐❛❧ ❞✐str✐❜✉t✐♦♥ ✐s r❡♣r❡s❡♥t❡❞ ✇✐t❤ ❛ ❜✐♦♠❛ss ❝♦♥❝❡♥✲

tr❛t✐♦♥ ✜❡❧❞ ✇❤✐❝❤ ❞②♥❛♠✐❝ ✐s ❣✐✈❡♥ ❜② ❛ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠❛ss ❜❛❧❛♥❝❡ ❡q✉❛t✐♦♥✳

❚❤❡ ♥✉tr✐❡♥t ❞②♥❛♠✐❝ ✐♥ ❜♦t❤ ♠♦❞❡❧s ✐s r❡♣r❡s❡♥t❡❞ ✐❞❡♥t✐❝❛❧❧② ✉s✐♥❣ ❛ ❞✐✛✉s✐♦♥✲

r❡❛❝t✐♦♥ ♠❛ss ❜❛❧❛♥❝❡ ❡q✉❛t✐♦♥✳ ❚❤❡ ♠♦❞❡❧s ❞✐✛❡r ❡ss❡♥t✐❛❧❧② ❜② t❤❡ ✇❛② t❤❡② r❡♣✲

r❡s❡♥t t❤❡ ❜✐♦♠❛ss ✭❞✐s❝r❡t❡ ✈❡rs✉s ❝♦♥t✐♥✉♦✉s✮ ❛♥❞ t❤❡ ❜✐♦♠❛ss✲r❡❧❛t❡❞ ♣r♦❝❡ss❡s✱

❡s♣❡❝✐❛❧❧② ❜✐♦♠❛ss r❡❞✐str✐❜✉t✐♦♥✳ ❚❤❡ ❣r♦✇t❤ ♦❢ t❤❡ ❜❛❝t❡r✐❛ ✐♥❝r❡❛s❡s t❤❡ ❧♦❝❛❧

❞❡♥s✐t② ♦❢ t❤❡ ❜✐♦♠❛ss ✇❤✐❝❤ ♥❡❡❞s t♦ ❜❡ r❡❞✐str✐❜✉t❡❞ ♦✈❡r s♣❛❝❡✳ ■♥ t❤❡ ■❇▼ r✉❧❡s

❛r❡ s❡t t♦ ♣❧❛❝❡ t❤❡ ♥❡✇❜♦r♥ ❝❡❧❧ ❝❧♦s❡ t♦ t❤❡ ♠♦t❤❡r ❝❡❧❧ ❛♥❞ t❤❡ ✜♥❛❧ ❞✐str✐❜✉t✐♦♥

♦❢ ❜❛❝t❡r✐❛ r❡s✉❧ts ❢r♦♠ t❤❡ s❡❧❢✲♦r❣❛♥✐③❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s t❤r♦✉❣❤ ❛ s❤♦✈✐♥❣

♣r♦❝❡ss✳ ❚❤✐s ♠❡❝❤❛♥✐s♠s ✐s ❞❡s❝r✐❜❡❞ ✐♥ t❤❡ ❆▼▼s ♣r♦♣♦s❡❞ ✐♥ ❬❊❜❡r❧ ✷✵✵✶❪ ❛s

❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞✐✛✉s✐♦♥✳ ❚❤❡ ❜✐♦♠❛ss ❞✐✛✉s✐♦♥ ✐♥❝r❡❛s❡s ✇✐t❤ t❤❡ ✐♥❝r❡❛s❡ ♦❢

t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ❜✐♦♠❛ss✳

❲❡ s❤❛❧❧ ♥♦t❡ t❤❛t ❛♥ ❛❧t❡r♥❛t✐✈❡ t♦ t❤❡ ❛❣❣r❡❣❛t❡❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠❛t❤❡♠❛t✲

✐❝❛❧ ♠♦❞❡❧ ♣r♦♣♦s❡❞ ✐♥ ❬❊❜❡r❧ ✷✵✵✶❪ ✐s t♦ ❝♦♥s✐❞❡r t❤❡ ❜✐♦♠❛ss ❛s ❛ ✈✐s❝♦✉s ✢✉✐❞

❛s ✐♥ t❤❡ ❉❝❦❡r②✲❑❧❛♣♣❡r ♠♦❞❡❧ ❬❉♦❝❦❡r② ✷✵✵✶❪❬❈♦❣❛♥ ✷✵✵✹❪✳ ❚❤❡ ❜✐♦♠❛ss ✐s t❤❡♥

❞❡s❝r✐❜❡❞ ✇✐t❤ ❛ ❞❡♥s✐t② ❛♥❞ ❛ ♣r❡ss✉r❡ ✜❡❧❞s✳ ❚❤❡ ❣r♦✇t❤ ♦❢ t❤❡ ❜✐♦♠❛ss ✐♥❝r❡❛s❡s

t❤❡ ❧♦❝❛❧ ♣r❡ss✉r❡ ✐♥❞✉❝✐♥❣ ❛♥ ❛❞✈❡❝t✐✈❡ tr❛♥s♣♦rt ♦❢ t❤❡ ❜✐♦♠❛ss✳ ❚❤❡ ❜✐♦♠❛ss

❛❞✈❡❝t✐✈❡ ✈❡❝t♦r u ✐s ❧✐♥❦❡❞ t♦ t❤❡ ❧♦❝❛❧ ♣r❡ss✉r❡ ❣r❛❞✐❡♥t ∇p t❤r♦✉❣❤ t❤❡ ❉❛r❝②

❧❛✇✿

u = −λ∇p ✭✷✳✶✮

✇❤❡r❡ λ ✐s t❤❡ ❉❛r❝② ❝♦♥st❛♥t✳ ❈♦♠♣❛r❡❞ t♦ t❤❡ ❉❘▼ ♣r♦♣♦s❡❞ ❜② ❊❜❡r❧

❬❊❜❡r❧ ✷✵✵✶❪✱ t❤✐s ♠♦❞❡❧ ✐s ♠✉❝❤ ♠♦r❡ ❛❝❝❡♣t❡❞ ❛♥❞ ❤❛s ❜❡❡♥ ❡①t❡♥❞❡❞ t♦ ♠✉❧t✐♣❧❡

♠✐❝r♦❜✐❛❧ t②♣❡s ❬❆❧♣❦✈✐st ✷✵✵✼❪ ❚❤❡ ❉♦❝❦❡r②✲❑❧❛♣♣❡r ♠♦❞❡❧ ❬❉♦❝❦❡r② ✷✵✵✶❪ ❤♦✇❡✈❡r

✐♥✈♦❧✈❡s ❛♥ ❛❞❞✐t✐♦♥❛❧ st❛t❡ ✈❛r✐❛❜❧❡ ✭♣r❡ss✉r❡ p✮ ❛♥❞ ♠♦r❡ ❝♦♠♣❧❡① ❜♦✉♥❞❛r✐❡s

❝♦♥❞✐t✐♦♥s ❛t t❤❡ ❜✐♦✜❧♠✴❜✉❧❦ ✐♥t❡r❢❛❝❡✳ ❋♦r s✐♠♣❧✐❝✐t② ✇❡ ❝♦♥s✐❞❡r t❤❡ ❊❜❡r❧ ♠♦❞❡❧

✐♥ t❤✐s ❝❤❛♣t❡r✳

✷✳✷ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

❲❡ ❞❡s❝r✐❜❡ ❛♥ ■❇▼ ❢♦r ❛ s②st❡♠ ✐♥✐t✐❛❧❧② ❢♦r♠❡❞ ✇✐t❤ ❛ ❜❛❝t❡r✐❛❧ ❝❡❧❧ ❧♦❝❛t❡❞ ✐♥

t❤❡ ❝❡♥t❡r ❛ t✇♦ ❞✐♠❡♥s✐♦♥❛❧ sq✉❛r❡❞ ❞♦♠❛✐♥✳ ❚❤❡ ♠♦❞❡❧ ✐s ❛ s✐♠♣❧✐✜❡❞ ✈❡rs✐♦♥ ♦❢

❑r❡❢t✬s ■❇▼ ❇❛❝s✐♠ s✐♠✉❧❛t✐♥❣ t❤❡ ❣r♦✇t❤ ♦❢ ❛ s✐♥❣❧❡ ❊s❝❤❡r✐❝❤✐❛ ❝♦❧✐ ❝❡❧❧ ✐♥t♦ ❛

❝♦❧♦♥②❬❑r❡❢t ✶✾✾✽❪✳

Page 27: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✹

❈❤❛♣t❡r ✷✳ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

❋✐❣✉r❡ ✷✳✶✿ ❩♦♦♠❡❞ ✈✐❡✇ ♦❢ t❤❡ ■❇▼ s♣❛t✐❛❧ ❞♦♠❛✐♥✿ ❜❛❝t❡r✐❛❧ ❝❡❧❧s ✭❞✐s❝s✮ ❛♥❞

♣❛t❝❤❡s ✭sq✉❛r❡s ✇✐t❤ ❛ s✐❞❡ ∆l✮✳ ❆ ❜❛❝t❡r✐✉♠ ✇✐t❤ ❝♦♥t✐♥✉♦✉s ❝♦♦r❞✐♥❛t❡s x✱y ✐s

❝♦♥t❛✐♥❡❞ ✐♥ t❤❡ ♣❛t❝❤ i = floor(x/∆l)✱ j = floor(y/∆l)✳

✷✳✸ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥

✷✳✸✳✶ ❖✈❡r✈✐❡✇

✷✳✸✳✶✳✶ P✉r♣♦s❡

❚❤❡ ❛✐♠ ♦❢ t❤❡ ♠♦❞❡❧ ✐s t♦ ✐♥✈❡st✐❣❛t❡ ❤♦✇ ❝♦❧♦♥② ♣❛tt❡r♥s ❡♠❡r❣❡ ❢r♦♠ t❤❡ ❧♦❝❛❧

✐♥t❡r❛❝t✐♦♥s ❜❡t✇❡❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s✳

✷✳✸✳✶✳✷ ❙t❛t❡ ✈❛r✐❛❜❧❡s

❚❤❡ ♠♦❞❡❧ ✐s ❛ t✇♦✲❞✐♠❡♥s✐♦♥❛❧ r❡♣r❡s❡♥t❛t✐♦♥ ♦❢ ❛ ❞♦♠❛✐♥ ❛♥❞ ❝♦♠♣r✐s❡s t✇♦ ❡♥t✐✲

t✐❡s✿ ❜❛❝t❡r✐❛❧ ❝❡❧❧s ❛♥❞ t❤❡✐r ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ✭♣❛t❝❤❡s✮ ✭✜❣✉r❡ ✷✳✶✮✳ ❇❛❝t❡r✐❛❧ ❝❡❧❧s

❛r❡ r❡♣r❡s❡♥t❡❞ ❛s ❞✐s❝s✳ ❚❤❡② ❛r❡ ❝❤❛r❛❝t❡r✐③❡❞ ❜② t❤❡ st❛t❡ ✈❛r✐❛❜❧❡s✿ ❝♦♥t✐♥✉♦✉s

♣♦s✐t✐♦♥ (x, y)✱ ✐♥❞✐✈✐❞✉❛❧ ♠❛ss (m) ❛♥❞ ✐♥❞✐✈✐❞✉❛❧ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡ (r)✭t❛❜❧❡

✷✳✶✮✳

❆ ♣❛t❝❤ (i, j) ✐s ❝❤❛r❛❝t❡r✐③❡❞ ❜② t✇♦ st❛t❡ ✈❛r✐❛❜❧❡s✿ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥

(s(i, j)) ❛♥❞ ❛ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡ (rs(i, j))✳ ❚❤❡ ❧❛t❡r ❝♦rr❡s♣♦♥❞s t♦ t❤❡ s✉♠ ♦❢

✉♣t❛❦❡ r❛t❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❝♦♥t❛✐♥❡❞ ✇✐t❤✐♥ t❤❡ ♣❛t❝❤ ✭t❛❜❧❡ ✷✳✶✮✳

✷✳✸✳✶✳✸ Pr♦❝❡ss ❖✈❡r✈✐❡✇ ❛♥❞ s❝❤❡❞✉❧✐♥❣

❲❡ ❝♦♥s✐❞❡r ❛ ✈✐rt✉❛❧ ♣♦♣✉❧❛t✐♦♥ ♦❢ ❜❛❝t❡r✐❛❧ ❝❡❧❧s ✐♥✐t✐❛t❡❞ ✇✐t❤ ❛ s✐♥❣❧❡ ❝❡❧❧ ✐♥ t❤❡

❝❡♥t❡r ♦❢ sq✉❛r❡❞ ❞♦♠❛✐♥✳ ❲❡ s✉♣♣♦s❡ t❤❛t t❤❡ ❞♦♠❛✐♥ ❤♦❧❞s ❛♥ ✐♥✐t✐❛❧ st♦❝❦ ♦❢ ❛

Page 28: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✷✳✸✳ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✶✺

❱❛r✐❛❜❧❡ ❉❡s❝r✐♣t✐♦♥

❇❛❝t❡r✐✉♠ st❛t❡ x✱ y ❈♦♥t✐♥✉♦✉s ♣♦s✐t✐♦♥ ♦❢ t❤❡ ❝❡♥t❡r ♦❢

t❤❡ ❜❛❝t❡r✐✉♠

m ▼❛ss

r ■♥❞✐✈✐❞✉❛❧ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡

P❛t❝❤ st❛t❡ s ❙✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥

rs ❘❡❛❝t✐♦♥ r❛t❡ ✭s✉♠ ♦❢ s✉❜str❛t❡ ✉♣✲

t❛❦❡ r❛t❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❝♦♥✲

t❛✐♥❡❞ ✇✐t❤✐♥ t❤❡ ♣❛t❝❤✮

❚❛❜❧❡ ✷✳✶✿ ❙t❛t❡ ✈❛r✐❛❜❧❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

P❛r❛♠❡t❡rs ❉❡s❝r✐♣t✐♦♥ ❯♥✐t ❱❛❧✉❡

s0 ■♥✐t✐❛❧ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ kg/m2 1.0

N0 ■♥✐t✐❛❧ ♥✉♠❜❡r ♦❢ ✐♥❞✐✈✐❞✉❛❧s 1

m0 ■♥✐t✐❛❧ ♠❛ss ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ kg 10−9

❚❛❜❧❡ ✷✳✷✿ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✐♥✐t✐❛❧✐③❛t✐♦♥

❞✐✛✉s✐✈❡ s✉❜str❛t❡ ❝♦♥s✉♠❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛✳ ■♥ t❤❡ ♠♦❞❡❧✱ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❜❛❝t❡r✐❛❧

❝❡❧❧ ❣r♦✇s ❜② ✉♣t❛❦✐♥❣ s✉❜str❛t❡ ❢r♦♠ ✐ts ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ❛t ❛ r❛t❡ t❤❛t ❞❡♣❡♥❞s

♦♥ t❤❡ ❧♦❝❛❧ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ❛♥❞ ♦♥ ✐ts ✐♥❞✐✈✐❞✉❛❧ ♠❛ss✳ ■❢ t❤❡ ♠❛ss ♦❢

t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❜❡❝♦♠❡s ❤✐❣❤❡r t❤❛♥ ❛ ❝r✐t✐❝❛❧ ✈❛❧✉❡✱ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❞✐✈✐❞❡s ✐♥t♦ t✇♦

✐❞❡♥t✐❝❛❧ ❛❞❥❛❝❡♥t ✐♥❞✐✈✐❞✉❛❧s✳

✷✳✸✳✷ ❉❡s✐❣♥ ❈♦♥❝❡♣ts

• ❊♠❡r❣❡♥❝❡✿ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ♦❢ t❤❡ ❝♦❧♦♥② ❡♠❡r❣❡s ♦✉t ♦❢ t❤❡ ❧♦❝❛❧ ✐♥t❡r✲

❛❝t✐♦♥ ❜❡t✇❡❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ ❜❡t✇❡❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ t❤❡✐r ❡♥✈✐r♦♥✲

♠❡♥t✳

• ■♥t❡r❛❝t✐♦♥✿ ✐♥❞✐✈✐❞✉❛❧s ✐♥t❡r❛❝t ✇✐t❤ t❤❡ ❡♥✈✐r♦♥♠❡♥t ❜② ✉♣✲t❛❦✐♥❣ s✉❜✲

str❛t❡✳ ❚❤❡② ❝♦♠♣❡t❡ ✇✐t❤ ❡❛❝❤ ♦t❤❡rs ❢♦r s✉❜str❛t❡ ❛♥❞ ❢♦r s♣❛❝❡✳

• ❙t♦❝❤❛st✐❝✐t②✿ t❤❡ ♦♥❧② st♦❝❤❛st✐❝ ♣r♦❝❡ss t❤❛t ✇❡ ✐♥❝❧✉❞❡❞ ✐♥ t❤❡ ♠♦❞❡❧ ✐s

t❤❡ s❡❧❡❝t✐♦♥ ♦❢ t❤❡ ❧♦❝❛t✐♦♥ ♦❢ t❤❡ ♥❡✇❜♦r♥ ✐♥❞✐✈✐❞✉❛❧ ❛❢t❡r ❛ ❞✐✈✐s✐♦♥ ❡✈❡♥t✳

✷✳✸✳✸ ❉❡t❛✐❧s

✷✳✸✳✸✳✶ ■♥✐t✐❛❧✐③❛t✐♦♥

❲❡ ✐♥✐t✐❛❧✐③❡ t❤❡ ♠♦❞❡❧ ✇✐t❤ ❛ s✐♥❣❧❡ ✐♥❞✐✈✐❞✉❛❧ N0 = 1 ❧♦❝❛t❡❞ ❛t t❤❡ ❝❡♥t❡r ♦❢ t❤❡

❞♦♠❛✐♥ x0 = L/2, y0 = L/2 ❛♥❞ ❤❛✈✐♥❣ ❛♥ ✐♥✐t✐❛❧ ♠❛ss m0✳ ■♥✐t✐❛❧❧②✱ t❤❡ s✉❜str❛t❡

✐s ✉♥✐❢♦r♠❧② ❞✐str✐❜✉t❡❞ ♦✈❡r t❤❡ ❞♦♠❛✐♥✳ ❚❤❡ ✐♥✐t✐❛❧ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ✐s s0❢♦r ❛❧❧ s♣❛t✐❛❧ ♣❛t❝❤❡s (i, j)✳

Page 29: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✻

❈❤❛♣t❡r ✷✳ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

✷✳✸✳✸✳✷ ❙✉❜♠♦❞❡❧s

• ❇❛❝t❡r✐❛ ❣r♦✇t❤ ♠♦❞❡❧✿ ❣r♦✇t❤ ✐s ♠♦❞❡❧❡❞ ❜② ❛❧❧♦✇✐♥❣ t❤❡ ✐♥❞✐✈✐❞✉✲

❛❧s ♠❛ss t♦ ✐♥❝r❡❛s❡ ♣r♦♣♦rt✐♦♥❛❧❧② t♦ ✐♥❞✐✈✐❞✉❛❧s ♥✉tr✐❡♥t ✉♣t❛❦❡ r❛t❡✳ ❆s

t❤❡ ♥✉tr✐❡♥t ❤❛s t♦ ❜❡ t❛❦❡♥ ✉♣ t❤r♦✉❣❤ t❤❡ ❝❡❧❧✬s s✉r❢❛❝❡✱ ✐t ✐s str❛✐❣❤t❢♦r✲

✇❛r❞ t♦ ❛ss✉♠❡ t❤❛t ✉♣t❛❦❡ ✐s ♣r♦♣♦rt✐♦♥❛❧ t♦ s✉r❢❛❝❡ ❛r❡❛ ❬❇✉tt♦♥ ✶✾✾✸❪

❬❑r❡❢t ✶✾✾✽❪✳ ❚❤❡ ❝❤❛♥❣❡s ♦❢ s✉r❢❛❝❡✲t♦✲✈♦❧✉♠❡ r❛t✐♦ ❞✉r✐♥❣ t❤❡ ❝❡❧❧ ❝②❝❧❡

✇♦✉❧❞ r❡s✉❧t ✐♥ ♥♦♥✲❡①♣♦♥❡♥t✐❛❧✐t② ♦❢ t❤❡ ❝❡❧❧✬s ❣r♦✇t❤ ❝✉r✈❡ ✐❢ ✉♣t❛❦❡ ❧✐♠✐ts

❣r♦✇t❤ ❬❑r❡❢t ✶✾✾✽❪✳ ❍♦✇❡✈❡r✱ ❛❢t❡r ❛ ❧♦♥❣ ❝♦♥tr♦✈❡rs②✱ ✐t ✐s ♥♦✇ ❣❡♥❡r❛❧❧② ❛s✲

s✉♠❡❞ t❤❛t t❤❡ ❣r♦✇t❤ ♦❢ ❛ s✐♥❣❧❡ ❝❡❧❧ ❞♦❡s ♥♦t ❞❡✈✐❛t❡ s✐❣♥✐✜❝❛♥t❧② ❢r♦♠ t❤❡

❡①♣♦♥❡♥t✐❛❧ ❣r♦✇t❤ ❧❛✇ ❬❑♦❝❤ ✶✾✾✸❪✳ ❚❤✉s✱ ✇❡ s✉♣♣♦s❡ t❤❛t ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧

✉♣t❛❦❡s s✉❜str❛t❡ ♣r♦♣♦rt✐♦♥❛❧❧② t♦ ✐ts ♠❛ss ❛♥❞ ❛❝❝♦r❞✐♥❣ t♦ ▼♦♥♦❞ ❣r♦✇t❤

❦✐♥❡t✐❝✳ ❚❤❡ ♥❡t ❣r♦✇t❤ r❛t❡ ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧ ✐s t❤❡♥ ❣✐✈❡♥ ❜②✿

dm

dt= mµmax

s

s+ ks✭✷✳✷✮

✇❤❡r❡ m ✐s t❤❡ ♠❛s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✱ s ✐s t❤❡ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ✐♥ t❤❡

s♣❛t✐❛❧ ♣❛t❝❤ ❝♦rr❡s♣♦♥❞✐♥❣ t♦ t❤❡ ❝❡❧❧ ♣♦s✐t✐♦♥✱ µmax ✐s t❤❡ ♠❛①✐♠✉♠ ❣r♦✇t❤

r❛t❡✱ ks ✐s t❤❡ ❛✣♥✐t② ❢❛❝t♦r ♦r t❤❡ ❤❛❧❢✲s❛t✉r❛t✐♦♥ ❝♦♥st❛♥t ❛s ks ❝♦rr❡s♣♦♥❞s

t♦ t❤❡ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ❢♦r ✇❤✐❝❤ t❤❡ ❣r♦✇t❤ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐s

µmax/2✳

• ❇❛❝t❡r✐❛ ❞✐✈✐s✐♦♥✿ ♦♥❡ ♦❢ t❤❡ s✐♠♣❧❡st ✇❛② t♦ ♠♦❞❡❧ ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥ ✇✐t❤

❛♥② ♣r❡t❡♥s❡ t♦ r❡❛❧✐t② ✐s t♦ ♠❛❦❡ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧ ❞✐✈✐❞❡ ♦♥❝❡ ✐ts ♠❛ss

r❡❛❝❤❡s ❛ ❝r✐t✐❝❛❧ ✈❛❧✉❡ ✭❞❡♥♦t❡❞ mdc✮✳ ❚❤❡ ♠♦t❤❡r ❝❡❧❧ ✐s ❞✐✈✐❞❡❞ ✐♥t♦ t✇♦

❞❛✉❣❤t❡r ❝❡❧❧s ❡❛❝❤ ❤❛✈✐♥❣ ❛ ♠❛ss ❝♦rr❡s♣♦♥❞✐♥❣ t♦ ❤❛❧❢ ♦❢ t❤❡ ♠❛ss ♦❢ t❤❡

♠♦t❤❡r ❝❡❧❧✳ ❖♥❡ ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧s ✐s ♣❧❛❝❡❞ ❛t t❤❡ ♣♦s✐t✐♦♥ ♦❢ t❤❡ ♠♦t❤❡r

❝❡❧❧ ✇❤✐❧❡ t❤❡ s❡❝♦♥❞ ♦♥❡ ✐s ♣❧❛❝❡❞ r❛♥❞♦♠❧② ✐♥ ❛♥ ❛❞❥❛❝❡♥t ♣♦s✐t✐♦♥✳

• ❙❤♦✈✐♥❣ r❡❧❛①❛t✐♦♥ ♠♦❞❡❧✿ ❛❞❥❛❝❡♥t ❜❛❝t❡r✐❛ ♠❛② ♦✈❡r❧❛♣ ✇❤❡♥ t❤❡✐r s✐③❡

✐♥❝r❡❛s❡ ♦r ❛❢t❡r ❛ ❞✐✈✐s✐♦♥ ❡✈❡♥t✳ ❚❤❡ ♦✈❡r❧❛♣ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐s r❡❧❛①❡❞ ✉s✐♥❣

❛♥ ❛❧❣♦r✐t❤♠ t❤❛t ♠✐♠✐❝s ❛ s❤♦✈✐♥❣ ♠❡❝❤❛♥✐s♠ ❛❞❛♣t❡❞ ❢r♦♠ ❬❑r❡❢t ✶✾✾✽❪✳ ■❢

❛ ❜❛❝t❡r✐✉♠ ✇✐t❤ r❛❞✐✉s a ✐s ♦✈❡r❧❛♣♣❡❞ ✇✐t❤ n ♥❡✐❣❤❜♦r✐♥❣ ❝❡❧❧s✱ ✐t ✐s ❞✐s♣❧❛❝❡❞

✇✐t❤ ❛ s❤♦✈✐♥❣ ✈❡❝t♦r d ❝❛❧❝✉❧❛t❡❞ ✉s✐♥❣ t❤❡ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥ ❛❞❛♣t❡❞ ❢r♦♠

❬❑r❡❢t ✷✵✵✶❪✿

d =∑

k=1:n

a+ ak − dk2

uk ✭✷✳✸✮

ak ✐s t❤❡ r❛❞✐✉s ♦❢ t❤❡ ♥❡✐❣❤❜♦r ❝❡❧❧ k✱ dk ✐s t❤❡ ❊✉❝❧✐❞❡❛♥ ❞✐st❛♥❝❡ ❢r♦♠ t❤❡

❝❡♥t❡r ♦❢ t❤❡ ❜❛❝t❡r✐✉♠ t♦ t❤❡ ❝❡♥t❡r t❤❡ kth ♥❡✐❣❤❜♦r✐♥❣ ❝❡❧❧ ❛♥❞ uk ✐s ❛

✈❡❝t♦r ❞✐r❡❝t❡❞ ❢r♦♠ t❤❡ ❝❡♥t❡r ♦❢ ♥❡✐❣❤❜♦r ❜❛❝t❡r✐✉♠ k t♦✇❛r❞s t❤❡ ❝❡♥t❡r ♦❢

t❤❡ ❜❛❝t❡r✐✉♠ ❛♥❞ ❤❛✈✐♥❣ ❛ ✉♥✐t❛r② ♥♦r♠✳

• ▲♦❝❛❧ r❡❛❝t✐♦♥ r❛t❡ ❝❛❧❝✉❧❛t✐♦♥✿ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❧♦❝❛t❡❞ ✇✐t❤✐♥ ❛ ♣❛t❝❤

❝♦♥s✉♠❡s ❛♥ ❛♠♦✉♥t ♦❢ t❤❡ s✉❜str❛t❡ ❛✈❛✐❧❛❜❧❡ ✇✐t❤✐♥ t❤❡ ♣❛t❝❤✳ ■❢ ❛ ♣❛t❝❤

Page 30: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✷✳✹✳ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ s✐♠✉❧❛t✐♦♥ ✶✼

❝♦♥t❛✐♥s ♠♦r❡ t❤❛♥ ♦♥❡ ✐♥❞✐✈✐❞✉❛❧✱ t❤❡♥ ✇❡ ❝❛❧❝✉❧❛t❡ t❤❡ ♣❛t❝❤ r❡❛❝t✐♦♥ r❛t❡

❜② s✉♠♠✐♥❣ t❤❡ ✉♣t❛❦❡ r❛t❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❝♦♥t❛✐♥❡❞ ✇✐t❤✐♥ t❤❡ ♣❛t❝❤✿

rs(i, j) =1

∆A

Nk∑

k=1

(

dm

dt

)

k

✭✷✳✹✮

✇❤❡r❡ ∆A ✐s t❤❡ ❛r❡❛ ♦❢ t❤❡ ♣❛t❝❤✱ Nk t❤❡ ♥✉♠❜❡r ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✇✐t❤✐♥ t❤❡

♣❛t❝❤

• ❙✉❜str❛t❡ ♠❛ss ❜❛❧❛♥❝❡✿ ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡ s✉❜str❛t❡ ✐s ♣r♦✈✐❞❡❞ t♦ t❤❡

❞♦♠❛✐♥ t❤r♦✉❣❤ t❤❡ ❜♦✉♥❞❛r② ❜② ✜①✐♥❣ ❛ ❝♦♥st❛♥t ❧❡✈❡❧ ♦❢ s✉❜str❛t❡ ❛t t❤❡

❜♦✉♥❞❛r②✳ ■♥s✐❞❡ t❤❡ ❞♦♠❛✐♥✱ ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡ s✉❜str❛t❡ ✐s tr❛♥s♣♦rt❡❞

❜② ❞✐✛✉s✐♦♥✳ ❚❤❡ s✉❜str❛t❡ s♣❛t✐❛❧ ❞✐str✐❜✉t✐♦♥ ❝❛♥ ❜❡ ♦❜t❛✐♥❡❞ ♦❜t❛✐♥❡❞ ❜②

s♦❧✈✐♥❣ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ❡q✉❛t✐♦♥✿

∂s

∂t= Ds∇

2s− rs ✭✷✳✺✮

✇❤❡r❡ Ds ✐s t❤❡ ♥✉tr✐❡♥t ❞✐✛✉s✐♦♥ ❢❛❝t♦r ❛♥❞ rs t❤❡ ♥✉tr✐❡♥t ❝♦♥s✉♠♣t✐♦♥ r❛t❡✳

❊q✉❛t✐♦♥ ❡q✿s✉❜str❛t❡ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✇✐t❤ t❤❡ ❛ ✉♥✐❢♦r♠ ✐♥✐t✐❛❧ ❝♦♥❞✐t✐♦♥s

s(x, t, t = 0) = s0 ❛♥❞ ✐♠♣♦s❡❞ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ sbound ♦♥ t❤❡ ❜♦✉♥❞✲

❛r②✳ ❊q✉❛t✐♦♥ ✷✳✺ ❝❛♥♥♦t ❜❡ s♦❧✈❡❞ ❛♥❛❧②t✐❝❛❧❧② ❜✉t r❛t❤❡r ✐s ❞✐s❝r❡t✐③❡❞ ✇✐t❤

r❡s♣❡❝t t♦ t✐♠❡ ❛♥❞ s♣❛❝❡ ✇❤✐❝❤ ②✐❡❧❞s t❤❡ ❢♦❧❧♦✇✐♥❣ s❡t ♦❢ ❛❧❣❡❜r❛✐❝ ❡q✉❛t✐♦♥s✿

st+dt(i, j) = st(i, j) +dtD

∆l2[st(i− 1, j) + st(i+ 1, j) + ✭✷✳✻✮

+st(i, j − 1) + st(i, j + 1)− 4st(i, j)]− dtr(i, j)

✇❤❡r❡ i, j ❛r❡ t❤❡ ❝♦♦r❞✐♥❛t❡s ♦❢ t❤❡ ✐♥t❡r♥❛❧ ♣❛t❝❤❡s✱ st(i, j) ❛♥❞ st+dt(i, j)

❛r❡ t❤❡ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥s ✇✐t❤✐♥ t❤❡ ♣❛t❝❤ (i, j) ❛t t✐♠❡ t ❛♥❞ t + dt

r❡s♣❡❝t✐✈❡❧②✳ ❊q✉❛t✐♦♥ ❣✐✈❡s t❤❡ ♥❡✇ s♣❛t✐❛❧ ❞✐str✐❜✉t✐♦♥ ♦❢ s✉❜str❛t❡ ❛s ❛

❢✉♥❝t✐♦♥ ♦❢ t❤❡ s✉❜str❛t❡ s♣❛t✐❛❧ ❞✐str✐❜✉t✐♦♥ ❛♥❞ t❤❡ ❜❛❝t❡r✐❛ ✉♣t❛❦❡ r❛t❡s ✐♥

t❤❡ ♣r❡✈✐♦✉s t✐♠❡✲st❡♣✳

✷✳✸✳✹ ▼♦❞❡❧ ♣❛r❛♠❡t❡rs

❯♥❧❡ss ❡①♣❧✐❝✐t❧② s♣❡❝✐✜❡❞ ✇❡ ❝♦♥s✐❞❡r t❤❡ ✈❛❧✉❡s ♦❢ t❤❡ ■❇▼ ♣❛r❛♠❡t❡rs ❛r❡ r❡♣♦rt❡❞

✐♥ t❛❜❧❡ ✷✳✸

✷✳✹ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ s✐♠✉❧❛t✐♦♥

❲❡ ❡①♣❧♦r❡ t❤❡ ❝♦❧♦♥② s♣❛t✐❛❧ ♣❛tt❡r♥ ❢♦r t✇♦ ❝♦❧♦♥② ❣r♦✇t❤ r❡❣✐♠❡s✱ ♥❛♠❡❧② t❤❡

✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ ❛♥❞ t❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡s✳ ❚❤❡ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡

✐♠♣❧✐❡s t❤❛t t❤❡ ❣r♦✇t❤ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐♥ t❤❡ ❝♦❧♦♥② ✐s ❧✐♠✐t❡❞ ❜② t❤❡✐r ❣r♦✇t❤

Page 31: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✽

❈❤❛♣t❡r ✷✳ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

P❛r❛♠❡t❡rs ❉❡s❝r✐♣t✐♦♥ ❯♥✐t ❱❛❧✉❡

❙♣❛t✐❛❧ ❞♦♠❛✐♥ ✲ µm ① µm 201 ① 201

∆x ❙♣❛t✐❛❧ ❞✐s❝r❡t✐③❛t✐♦♥ µm 5

∆t ❚✐♠❡ st❡♣ s variable

µmax ▼❛①✐♠✉♠ ❣r♦✇t❤ r❛t❡ s−1 10−4

ks ❆✣♥✐t② ❢❛❝t♦r kg/m2 0.01

Ds ❙✉❜str❛t❡ ❞✐✛✉s✐♦♥ ❝♦♥st❛♥t m2/s variable

Sbound ■♠♣♦s❡❞ ❜♦✉♥❞❛r② s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ kg/m2 1.0

md ▼❛ss ♦❢ t❤❡ ❜❛❝t❡r✐✉♠ ❛t ❞✐✈✐s♦♥ kg 2.0 10−9

ρ ❛r❡❛❧ ❞❡♥s✐t② ♦❢ ❛ ❜❛❝t❡r✐✉♠ kg/m2 290.0

❚❛❜❧❡ ✷✳✸✿ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs✳ ❚❤❡ s✉❜str❛t❡ ❞✐✛✉s✐♦♥ ❢❛❝t♦r ✐s

✈❛r✐❡❞ t♦ s✇✐t❝❤ ❢r♦♠ t❤❡ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ ❛♥❞ t❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ ❝❛s❡s✳ ❚❤❡

t✐♠❡✲st❡♣ ✐s ❛❞❛♣t❡❞ ❝♦♥s❡q✉❡♥t❧② t♦ ❡♥s✉r❡ t❤❡ ❝♦♥✈❡r❣❡♥❝❡ ♦❢ t❤❡ ❡①♣❧✐❝✐t ❊✉❧❡r

t✐♠❡ ❞✐s❝r❡t✐③❛t✐♦♥ s❝❤❡♠❡ ♦❢ t❤❡ s✉❜str❛t❡ ♠❛ss ❜❛❧❛♥❝❡ ❡q✉❛t✐♦♥

♣❛r❛♠❡t❡rs r❛t❤❡r t❤❛♥ ❜② t❤❡ ♥✉tr✐❡♥t ❛✈❛✐❧❛❜✐❧✐t②✳ ■♥ t❤✐s r❡❣✐♠❡✱ t❤❡ ♥✉tr✐❡♥t ✐s

tr❛♥s♣♦rt❡❞ ❛t ❛ s✉✣❝✐❡♥t r❛t❡ ❢r♦♠ t❤❡ ❜♦✉♥❞❛r② ♦❢ t❤❡ ❞♦♠❛✐♥ t♦ t❤❡ ❧♦❝❛t✐♦♥s

♦❢ t❤❡ ❜❛❝t❡r✐❛ ✳ ❚♦ ♦❜t❛✐♥ t❤✐s r❡❣✐♠❡ ✇❡ s❡t t❤❡ ♥✉tr✐❡♥t ❞✐✛✉s✐♦♥ r❛t❡ t♦ ❛

r❡❧❛t✐✈❡❧② ❤✐❣❤ ✈❛❧✉❡ Ds = 10−10m2/s✳ ❈♦♥✈❡rs❡❧②✱ ✐♥ t❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡✱

t❤❡ ❣r♦✇t❤ ♦❢ t❤❡ ❜❛❝t❡r✐❛ ✐s ❧✐♠✐t❡❞ ❜② t❤❡ ♥✉tr✐❡♥t ❛✈❛✐❧❛❜✐❧✐t②✳ ■♥ t❤✐s r❡❣✐♠❡✱ t❤❡

❜❛❝t❡r✐❛ ❡①♣❡r✐❡♥❝❡ ❧♦✇ ♥✉tr✐❡♥t ❝♦♥❝❡♥tr❛t✐♦♥s ❛♥❞ t❤❡✐r ❣r♦✇t❤ r❛t❡ ✐s ♠✉❝❤ ❧♦✇❡r

t❤❛♥ t❤❡✐r ♠❛①✐♠✉♠ ❣r♦✇t❤ r❛t❡ ✭❣✐✈❡♥ ❜② µmax✮✳ ❚❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡ ❝❛♥

❜❡ ♦❜t❛✐♥❡❞ ❜② s❡tt✐♥❣ t❤❡ s✉❜str❛t❡ ❞✐✛✉s✐♦♥ r❛t❡ t♦ ❛ ❧♦✇ ✈❛❧✉❡ ✭Ds = 10−12m2/s ✐♥

♦✉r ❝❛s❡✮✳ ❋✐❣✉r❡ ✷✳✷ ❛♥❞ ✜❣✉r❡ ✷✳✸ s❤♦✇ t❤❡ t✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ♦❢

t❤❡ ❝♦❧♦♥② s✐♠✉❧❛t❡❞ ❜② t❤❡ ■❇▼ ❢♦r ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ ❛♥ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡s

r❡s♣❡❝t✐✈❡❧②✳ ■♥ t❤❡ ❝❛s❡ ♦❢ t❤❡ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡ t❤❡ ❢♦r♠❡❞ ❝♦❧♦♥② ❤❛s ❛

r❡❣✉❧❛r r♦✉♥❞❡❞ s❤❛♣❡ ✇❤✐❧❡ ✐♥ t❤❡ ❝❛s❡ ♦❢ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡ t❤❡ s❤❛♣❡ ♦❢ t❤❡

❝♦❧♦♥② ✐s ✐rr❡❣✉❧❛r ❛♥❞ s❤♦✇s t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ✬✜♥❣❡rs✬✳ ❈❡❧❧s t❤❛t ❛r❡ ❝❧♦s❡r t♦ t❤❡

❜♦✉♥❞❛r② t❤❛♥ t❤❡✐r ♥❡✐❣❤❜♦rs ❡✐t❤❡r ❞✉❡ t♦ st♦❝❤❛st✐❝ ♣♦s✐t✐♦♥✐♥❣ ♦❢ ❞❛✉❣❤t❡r ❝❡❧❧s

❛❢t❡r ❛ ❞✐✈✐s✐♦♥ ❡✈❡♥t ♦r ❞✉❡ t♦ t❤❡ ✐♥❞✐✈✐❞✉❛❧s s❤♦✈✐♥❣ ❡❛❝❤ ♦t❤❡rs ❤❛✈❡ ❛ ❝♦♠♣❡t✐t✐✈❡

❛❞✈❛♥t❛❣❡ ❛s t❤❡② ❛r❡ ❧✐❦❡❧② t♦ ❡①♣❡r✐❡♥❝❡ ❛ ❤✐❣❤❡r s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ t❤❛♥

t❤❡✐r ♥❡✐❣❤❜♦rs ❛♥❞ t❤✉s ❣r♦✇ ❛t ❛ ❤✐❣❤❡r r❛t❡✳ ■t ✐s ✐♥t❡r❡st✐♥❣ t♦ ♥♦t❡ t❤❛t t❤❡

s❤❛♣❡ ♦❢ t❤❡ ❝♦❧♦♥② ✐s ♥♦t ❝♦❞❡❞ ✐♥ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❜✉t ✐s ❛♥ ❡♠❡r❣❡♥t

♣♦♣✉❧❛t✐♦♥✲❧❡✈❡❧ ♣r♦♣❡rt②✳ ■♥ t❤❡ ♥❡①t s❡❝t✐♦♥s ♦❢ t❤✐s ❝❤❛♣t❡r ✇❡ ✐♥✈❡st✐❣❛t❡ ✇❤❡t❤❡r

t❤❡s❡ ♣❛tt❡r♥s ❝❛♥ ❜❡ ②✐❡❧❞❡❞ ❜② t❤❡ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ ♣r♦♣♦s❡❞ ❜②

✐♥ ❬❊❜❡r❧ ✷✵✵✶❪✳

✷✳✺ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧

❊❜❡r❧ ❡t ❛❧✳ ❬❊❜❡r❧ ✷✵✵✶❪ ♣r♦♣♦s❡❞ ❛ ❝♦♥t✐♥✉✉♠ ❞❡t❡r♠✐♥✐st✐❝ ♠♦❞❡❧ ❜❛s❡❞ ♦♥ t❤❡

❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ❢r❛♠❡✇♦r❦ ❢♦r ♠♦❞❡❧✐♥❣ ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠s✳ ❚❤❡ ♠♦❞❡❧ r❡♣r❡s❡♥ts

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✷✳✺✳ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ ✶✾

✭❛✮ ■❇▼ time = 0h ✭❜✮ ■❇▼ time = 10h

✭❝✮ ■❇▼ time = 20h

❋✐❣✉r❡ ✷✳✷✿ ❚✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ♣❛tt❡r♥ s✐♠✉❧❛t❡❞ ✉s✐♥❣ t❤❡ ■❇▼ ✐♥ t❤❡

❝❛s❡ ♦❢ ❛ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞ r❡❣✐♠❡✬✳ ❙✐♠✉❧❛t✐♦♥ ❝♦♥❞✉❝t❡❞ ✇✐t❤ Ds = 10−10m2/s

❛♥❞ dt = 0.05s✳ ❚❤❡ ❣r❛② s❝❛❧❡ ✐♥❞✐❝❛t❡s t❤❡ ♥✉tr✐❡♥t ❝♦♥❝❡♥tr❛t✐♦♥ ✭❉❛r❦ ❣r❛②✿

s = 1.0kg/m2✱ ✇❤✐t❡✿ s = 0✮

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✷✵

❈❤❛♣t❡r ✷✳ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

✭❛✮ ■❇▼ time = 0h ✭❜✮ ■❇▼ time = 10h

✭❝✮ ■❇▼ time = 20h

❋✐❣✉r❡ ✷✳✸✿ ❚✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ♣❛tt❡r♥ s✐♠✉❧❛t❡❞ ✉s✐♥❣ t❤❡ ■❇▼ ✐♥ t❤❡

❝❛s❡ ♦❢ ❛ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞ r❡❣✐♠❡✬✳ ❙✐♠✉❧❛t✐♦♥ ❝♦♥❞✉❝t❡❞ ✇✐t❤ Ds = 10−12m2/s

❛♥❞ dt = 0.5s✳ ❚❤❡ ❣r❛② s❝❛❧❡ ✐♥❞✐❝❛t❡s t❤❡ ♥✉tr✐❡♥t ❝♦♥❝❡♥tr❛t✐♦♥✭❉❛r❦ ❣r❛②✿

s = 1.0kg/m2✱ ✇❤✐t❡✿ s = 0✮

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✷✳✺✳ ❆❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ ✷✶

t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ t❤❡ s✉❜str❛t❡ ✇✐t❤ t✇♦ ❞❡♥s✐t② ✜❡❧❞s ❞❡♥♦t❡❞ r❡s♣❡❝t✐✈❡❧② s(x, y)

❛♥❞ cb(x, y)✳

❈♦♠♣❛r❡❞ t♦ t❤❡ ■❇▼ t❤❛t ✇❡ ♣r❡s❡♥t❡❞ ❛❜♦✈❡✱ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

t❤❛t ✇❡ ❞❡s❝r✐❜❡ ✐♥ t❤✐s s❡❝t✐♦♥ ✐s ❛♥ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧✳ ❚❤❡ ♥♦✲

t✐♦♥ ♦❢ ❛❣❣r❡❣❛t❡❞ ♠♦❞❡❧ ✐♠♣❧✐❡s t❤❡ ✉s❡ ♦❢ ❛❣❣r❡❣❛t❡❞ st❛t❡ ✈❛r✐❛❜❧❡s ✇❤✐❝❤ ♣r♦✈✐❞❡

❛ ♠❛❝r♦s❝❛❧❡ ❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ st❛t❡ ♦❢ t❤❡ ❜❛❝t❡r✐❛✳ ■♥ ❛ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

t❤❡ ❛❣❣r❡❣❛t❡❞ st❛t❡ ✈❛r✐❛❜❧❡ ✐s ❜✐♦♠❛ss ❞❡♥s✐t② ✜❡❧❞ ✇❤✐❝❤ ❞❡t❡r♠✐♥❡s t❤❡ ❡①♣❡❝t❡❞

♠❛ss ❞❡♥s✐t② ♦❢ ❜❛❝t❡r✐❛ ✐♥ ❛♥② ❧♦❝❛t✐♦♥ x, y ♦❢ t❤❡ ❞♦♠❛✐♥✳

❚❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ❢♦r t❤❡ ❜❛❝t❡r✐❛ ❤❛s t❤❡ ❢♦❧❧♦✇✐♥❣ ❣❡♥❡r❛❧ ❢♦r♠✿

∂cb∂t

= ∇2(Dbcb) + rbcb ✭✷✳✼✮

❚❤❡ ✜rst t❡r♠ ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❞✐✛✉s✐♦♥ ♦❢ t❤❡ ❜✐♦♠❛ss ❛♥❞

t❤❡ s❡❝♦♥❞ t❡r♠ ❢♦r t❤❡ ♣r♦❞✉❝t✐♦♥ ♦❢ ❜✐♦♠❛ss✳ ❚❤❡ ✜rst t❡r♠ ❡①♣r❡ss❡s ❤♦✇ t❤❡ ♠❛ss

♦❢ t❤❡ ❜❛❝t❡r✐❛ ✐s r❡❞✐str✐❜✉t❡❞ ♦✈❡r ♥❡✐❣❤❜♦r✐♥❣ ♣❛t❝❤❡s✳ ❚❤✐s t❡r♠ ♣r♦✈✐❞❡s ❛ r♦✉❣❤

❛♣♣r♦①✐♠❛t✐♦♥ ❛t t❤❡ ♠❛❝r♦✲❧❡✈❡❧ ♦❢ t❤❡ s❤♦✈✐♥❣ ♣r♦❝❡ss ❞❡s❝r✐❜❡❞ ✐♥ t❤❡ ■❇▼✳ ❚❤❡

❡①♣❛♥s✐♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ❞❡♣❡♥❞s ♦♥ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ❜❛❝t❡r✐❛ ❛♥❞ t❛❦❡s ♣❧❛❝❡ ♦♥❧②

✐❢ t❤❡ ❜✐♦♠❛ss ❞❡♥s✐t② ❛♣♣r♦❛❝❤❡s ❛ ♣r❡s❝r✐❜❡❞ ♠❛①✐♠✉♠ ✈❛❧✉❡ ✇❤✐❝❤ ❡st❛❜❧✐s❤❡s ❛♥

✉♣♣❡r ❜♦✉♥❞ ❬❊❜❡r❧ ✷✵✵✶❪✳ ❊❧❜❡r❧ ❡t ❛❧✳ ❬❊❜❡r❧ ✷✵✵✶❪ ♣r♦♣♦s❡❞ ❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

❡①♣r❡ss✐♦♥ ❢♦r t❤❡ ❞✐✛✉s✐♦♥ ❢❛❝t♦r Db t❤❛t s❛t✐s✜❡s t❤✐s ❝♦♥❞✐t✐♦♥✳ ❚❤❡ ❡①♣r❡ss✐♦♥

t❛❦❡s t❤❡ ❢♦❧❧♦✇✐♥❣ ❣❡♥❡r✐❝ ❢♦r♠✿

Db = D0

cαb(Cbmax − cb)β

✭✷✳✽✮

✇✐t❤ α, β > 1 ❛♥❞ D0 t❤r❡❡ ♣❛r❛♠❡t❡rs ❛♥❞ Cbmax t❤❡ ♠❛①✐♠✉♠ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢

❜✐♦♠❛ss✳ ❚❤❡ ♣❤②s✐❝❛❧ ✐♥t❡r♣r❡t❛t✐♦♥ ♦❢ t❤✐s ❡q✉❛t✐♦♥ ✐s t❤❛t t❤❡ ❜✐♦♠❛ss ❞✐✛✉s✐✈✐t②

✈❛♥✐s❤❡s ❛s cb ❜❡❝♦♠❡s s♠❛❧❧ ❜✉t ✐♥❝r❡❛s❡s ❛s cb ❣r♦✇s ❞✉❡ t♦ s✉❜str❛t❡ ✉♣t❛❦❡✳

❊q✉❛t✐♦♥ ✷✳✼ ✐s ❝♦✉♣❧❡❞ t♦ t❤❡ ❢♦❧❧♦✇✐♥❣ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ❡q✉❛t✐♦♥ ♦❢ t❤❡ s✉❜str❛t❡✿

∂s

∂t= Ds∇

2s− rb ✭✷✳✾✮

✇❤❡r❡ s ✐s t❤❡ ❝♦♥❝❡♥tr❛t✐♦♥ ♦❢ s✉❜str❛t❡✱ Ds t❤❡ ❞✐✛✉s✐♦♥ ❢❛❝t♦r ♦❢ t❤❡ s✉❜str❛t❡

❛♥❞ rb t❤❡ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡✳ ❆ss✉♠✐♥❣ ❛ ▼♦♥♦❞ ❦✐♥❡t✐❝ ❛s ✐♥ t❤❡ ■❇▼✱ t❤❡

s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡ ✐s ❣✐✈❡♥ ❜②✿

rb = µmaxs

s+ kscb ✭✷✳✶✵✮

✇❤❡r❡ µmax ✐s t❤❡ ♠❛①✐♠✉♠ ❣r♦✇t❤ r❛t❡ ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❛♥❞ ks t❤❡ ❤❛❧❢✲

s❛t✉r❛t✐♦♥ ▼♦♥♦❞ ❝♦♥st❛♥t✳ ❆❞❞✐t✐♦♥❛❧❧②✱ ✇❡ ❝♦♥s✐❞❡r t❤❡ s❛♠❡ ❜♦✉♥❞❛r② ❛♥❞ ✐♥✐t✐❛❧

❝♦♥❞✐t✐♦♥s ❢♦r t❤❡ s✉❜str❛t❡ ❛s t❤♦s❡ t❤❛t ✇❡ ✉s❡❞ ✐♥ t❤❡ ■❇▼ ✭✜①❡❞ ❝♦♥❝❡♥tr❛t✐♦♥ ♦❢

s✉❜str❛t❡ ❛t t❤❡ ❜♦✉♥❞❛r② ❛♥❞ ✉♥✐❢♦r♠ ✐♥✐t✐❛❧ ❞✐str✐❜✉t✐♦♥ ♦❢ t❤❡ s✉❜str❛t❡✮✳ ❋♦r t❤❡

❜✐♦♠❛ss ✇❡ ❝♦♥s✐❞❡r ♣❡r✐♦❞✐❝ ❜♦✉♥❞❛r② ❝♦♥❞✐t✐♦♥s ❛♥❞ ✇❡ s✉♣♣♦s❡ t❤❛t ❛♥ ✐♥✐t✐❛❧

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✷✷

❈❤❛♣t❡r ✷✳ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

P❛r❛♠❡t❡rs ❉❡s❝r✐♣t✐♦♥ ❯♥✐t ❱❛❧✉❡

❙♣❛t✐❛❧ ❞♦♠❛✐♥ µm ① µm 201 ① 201

∆l µm 5

∆t s ✈❛r✐❛❜❧❡

µmax ▼❛①✐♠✉♠ ❣r♦✇t❤ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s s−1 10−4

ks ❆✣♥✐t② ❢❛❝t♦r kg/m2 0.01

Ds ❙✉❜str❛t❡ ❞✐✛✉s✐♦♥ ❝♦♥st❛♥t m2/s ✈❛r✐❛❜❧❡

Cbmax ▼❛①✐♠✉♠ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ❜✐♦♠❛ss m2/s 10−12

α ❞✐♠❡♥s✐♦♥❧❡ss 4.0

β ❞✐♠❡♥s✐♦♥❧❡ss 4.0

D0 m2/s ✈❛r✐❛❜❧❡

❚❛❜❧❡ ✷✳✹✿ ❉✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs

s❡❡❞ ♦❢ ❜✐♦♠❛ss ✐s ❧♦❝❛t❡❞ ✐♥ t❤❡ ❝❡♥tr❛❧ ♣❛t❝❤ ♦❢ t❤❡ ❞♦♠❛✐♥✳ ❚❤❡ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs

❛r❡ r❡♣♦rt❡❞ ✐♥ t❛❜❧❡ ✷✳✹✳

✷✳✻ ❈♦♠♣❛r✐♥❣ t❤❡ ■❇▼ ✇✐t❤ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥

♠♦❞❡❧

❲❡ ❝♦♠♣❛r❡ t❤❡ s✐♠✉❧❛t✐♦♥ r❡s✉❧ts ♦❢ ❜♦t❤ ♠♦❞❡❧s ❢♦r t❤❡ t✇♦ ❝♦❧♦♥② ❣r♦✇t❤

r❡❣✐♠❡s✳ ❚❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ♣r♦♣♦s❡❞ ✐♥ ❬❊❜❡r❧ ✷✵✵✶❪ ✐s ♥♦t ❞❡r✐✈❡❞ r✐❣✲

♦r♦✉s❧② ❢r♦♠ t❤❡ ♠✐❝r♦s❝❛❧❡ ❞②♥❛♠✐❝ t❤❛t ✇❡ ❝♦♥s✐❞❡r❡❞ ✐♥ t❤❡ ■❇▼✳ ■t ✉s❡s ❛♥

❛❞✲❤♦❝ ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡s❡ ♠✐❝r♦s❝❛❧❡ ♣r♦❝❡ss❡s ❜❛s❡❞ ♦♥ ❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

❡①♣r❡ss✐♦♥ ♦❢ t❤❡ ❜✐♦♠❛ss ❞✐✛✉s✐♦♥✳ ❚❤✐s ❢✉♥❝t✐♦♥ r❡q✉✐r❡s ❢♦✉r ♣❛r❛♠❡t❡rs α✱ β✱

D0 ❛♥❞ Cbmax ❛♥❞ ♦♥❡ ♦❢ t❤❡ ❞✐✣❝✉❧t✐❡s t❤❛t ❛r✐s❡s ✇❤❡♥ ✇❡ ❛tt❡♠♣t t♦ ❝♦♠♣❛r❡

t❤❡ ❉❘▼ ✇✐t❤ t❤❡ ■❇▼ ✐s t♦ ❛ss✐❣♥ ❛♣♣r♦♣r✐❛t❡ ✈❛❧✉❡s t♦ t❤❡s❡ ♣❛r❛♠❡t❡rs✳ ❚❤❡

♣❛r❛♠❡t❡r Cbmax ✭t❤❡ ♠❛①✐♠✉♠ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ❜✐♦♠❛ss✮ ❝❛♥ ❜❡ ❞❡❞✉❝❡❞ ❢r♦♠ t❤❡

■❇▼ s✐♠✉❧❛t✐♦♥s ❜② t❛❦✐♥❣ t❤❡ ♠❛①✐♠✉♠ ♠❡❛s✉r❡❞ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ❜✐♦♠❛ss✳ ❋♦r

t❤❡ ♣❛r❛♠❡t❡rs α ❛♥❞ β ✇❡ ✉s❡ t❤❡ ✈❛❧✉❡s s✉❣❣❡st❡❞ ❜② ❊❜❡r❧ ❡t ❛❧✳ ❬❊❜❡r❧ ✷✵✵✶❪✳

❚❤❡ ♣❛r❛♠❡t❡r D0✱ ✇❤✐❝❤ ✐s t❤❡ ♠❛①✐♠✉♠ ✈❛❧✉❡ ♦❢ t❤❡ ❜✐♦♠❛ss ❞✐✛✉s✐♦♥ ❢❛❝t♦r ✐s

❝❛❧✐❜r❛t❡❞ ✭♠❛♥✉❛❧❧②✮ t♦ ♦❜t❛✐♥ t❤❡ ❜❡st ✜t ❜❡t✇❡❡♥ t❤❡ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② ❜♦t❤

♠♦❞❡❧s✳ ❆ ❤✐❣❤ ✈❛❧✉❡ ♦❢ D0 ②✐❡❧❞s ❛ s✐♠✉❧❛t❡❞ ❝♦❧♦♥② t❤❛t ❡①♣❛♥❞s ❢❛st❡r t❤❛♥ ✐♥

t❤❡ ■❇▼✳

❋✐❣✉r❡ ✷✳✹ ❝♦♠♣❛r❡s t❤❡ s♥❛♣s❤♦ts ♦❢ t❤❡ ❝♦❧♦♥✐❡s s✐♠✉❧❛t❡❞ ✇✐t❤ t❤❡ ■❇▼ ❛♥❞ t❤❡

❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ✐♥ t❤❡ ❝❛s❡ ♦❢ ❛ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡✳ ❇♦t❤ ♠♦❞❡❧s ②✐❡❧❞

r♦✉♥❞❡❞ s❤❛♣❡❞ ❝♦❧♦♥✐❡s t❤❛t ❡①♣❛♥❞ ❡q✉❛❧❧② ✐♥ ❛❧❧ ❞✐r❡❝t✐♦♥s✳ ❚❤❡ ✢✉❝t✉❛t✐♦♥s ✐♥

t❤❡ ❝♦❧♦♥② s✐♠✉❧❛t❡❞ ✇✐t❤ t❤❡ ■❇▼ ❛r❡ ❞✉❡ t♦ t❤❡ st♦❝❤❛st✐❝ ♣♦s✐t✐♦♥✐♥❣ t❤❡ ♥❡✇❜♦r♥

✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡ ❧❡♥❣t❤ s❝❛❧❡ ♦❢ t❤❡s❡ ✢✉❝t✉❛t✐♦♥s ✐s r❡❧❛t✐✈❡❧② s♠❛❧❧ ❝♦♠♣❛r❡❞ t♦

t❤❡ s✐③❡ ♦❢ t❤❡ ❝♦❧♦♥②✱ ❛♥❞ ❛ s♠❛❧❧ ♥✉♠❜❡r ♦❢ s✐♠✉❧❛t✐♦♥s ✐s s✉✣❝✐❡♥t t♦ ❡①tr❛❝t t❤❡

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✷✳✼✳ ❉✐s❝✉ss✐♦♥ ✷✸

❞❡t❡r♠✐♥✐st✐❝ ❧✐♠✐t ②✐❡❧❞❡❞ ❜② t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧✳

❲❡ ❝♦♠♣❛r❡ t❤❡ s❤❛♣❡ ♦❢ t❤❡ s✐♠✉❧❛t❡❞ ❝♦❧♦♥✐❡s ✐♥ t❤❡ ❝❛s❡ ♦❢ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬

r❡❣✐♠❡✳ ■♥ t❤✐s ❝❛s❡✱ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❡①♣❡r✐❡♥❝❡ s✐❣♥✐✜❝❛♥t ❤❡t❡r♦❣❡♥❡✐t✐❡s ✐♥ t❤❡

s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ❛♥❞ ❝♦♥s❡q✉❡♥t❧② ❣r♦✇ ❛t ❞✐✛❡r❡♥t r❛t❡ ❞❡♣❡♥❞✐♥❣ ♦♥ t❤❡✐r

❧♦❝❛t✐♦♥ ✐♥ t❤❡ ❝♦❧♦♥②✳ ■♥❞✐✈✐❞✉❛❧s ❧♦❝❛t❡❞ ❛t t❤❡ ❡❞❣❡ ♦❢ t❤❡ ❝♦❧♦♥② t❡♥❞ t♦ ❤❛✈❡

❤✐❣❤ ❣r♦✇t❤ r❛t❡s ✐♥ ❝♦♠♣❛r✐s♦♥ t♦ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❧♦❝❛t❡❞ ❛t t❤❡ ❝❡♥t❡r ♦❢ t❤❡

❝♦❧♦♥②✳ ❋✐❣✉r❡ ✷✳✺ ❝♦♠♣❛r❡s s♥❛♣s❤♦ts ♦❢ t❤❡ s✐♠✉❧❛t❡❞ ❝♦❧♦♥② ♣❛tt❡r♥s✳ ❚❤❡ ■❇▼

♣❛tt❡r♥ ✐s ❛✈❡r❛❣❡❞ ♦✈❡r ✷✵ ■❇▼ s✐♠✉❧❛t✐♦♥s r✉♥ ✇✐t❤ ✇✐t❤ t❤❡ s❛♠❡ ♣❛r❛♠❡t❡r ❛♥❞

❞✐✛❡r❡♥t s❡❡❞s ❢♦r t❤❡ r❛♥❞♦♠ ♥✉♠❜❡r ❣❡♥❡r❛t♦r✳ ■♥ t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

t❤❡ ❝♦❧♦♥② ❡①♣❛♥❞s ❢♦r♠✐♥❣ ✜♥❣❡rs t❤❛t ❛r❡ ❞✐r❡❝t❡❞ t♦✇❛r❞s t❤❡ ❝❧♦s❡st ❞✐st❛♥❝❡s t♦

t❤❡ ❜♦✉♥❞❛r② ♦❢ t❤❡ ❞♦♠❛✐♥ ✇❤❡r❡ t❤❡ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ✐s t❤❡ ❤✐❣❤❡st✳ ❲❤✐❧❡

✬✜♥❣❡rs✬ ❛r❡ ❛❧s♦ ❢♦r♠❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ■❇▼ s✐♠✉❧❛t✐♦♥s✱ t❤❡② ❛r❡ ♥♦t ♦❜s❡r✈❡❞ ✐♥ t❤❡

❛✈❡r❛❣❡ ♣❛tt❡r♥ ❛♥❞ ❛r❡ ♥♦t ❧✐❦❡❧② t♦ ❜❡ ❞✐r❡❝t❡❞ t♦✇❛r❞s ❛♥② ♣r❡❢❡r❡♥t✐❛❧ ❞✐r❡❝t✐♦♥✳

❚❤❡② s❡❡♠s t♦ ♦❝❝✉r ❛t r❛♥❞♦♠ ❛♥❞ t❤❡ ❛✈❡r❛❣❡ ♣❛tt❡r♥ s❤♦✇s ❛ r♦✉♥❞✲s❤❛♣❡❞

❝♦❧♦♥②✳ ❚❤❡ ❝❧♦s❡st ❞✐st❛♥❝❡ t♦ t❤❡ ❜♦✉♥❞❛r② ✐s ♥♦t ♥❡❝❡ss❛r② t❤❡ ♦♥❡ ✇✐t❤ t❤❡

st❡❡♣❡st ♥✉tr✐❡♥t ❣r❛❞✐❡♥t ❛s t❤❡ ♥✉tr✐❡♥t ❞✐str✐❜✉t✐♦♥ ✐s ❤❡t❡r♦❣❡♥❡♦✉s ❛♥❞ ❝❛♥ ❜❡

❛✛❡❝t❡❞ ✇✐t❤ t❤❡ ✐rr❡❣✉❧❛r s❤❛♣❡ ♦❢ t❤❡ ❝♦❧♦♥②✳

❲❡ ❛ss❡ss❡❞ t❤❡ s❡♥s✐t✐✈✐t② ♦❢ t❤❡ ❉❘▼ ♣❛tt❡r♥ t♦ t❤❡ ✈❛r✐❛t✐♦♥ ♦❢ t❤❡ ♣❛r❛♠❡t❡r

D0✳ ❋✐❣✉r❡ ✷✳✻ s❤♦✇s t❤❡ ❛✈❡r❛❣❡ ♣❛tt❡r♥ ♦❜t❛✐♥❡❞ ✇✐t❤ t❤❡ ■❇▼ ❛t ❛♥ ✐♥t❡r♠❡❞✐❛t❡

t✐♠❡ t = 71h ❛♥❞ t❤❡ ♣❛tt❡r♥ ②✐❡❧❞❡❞ ❜② t❤❡ ❉❘▼ ❢♦r t❤r❡❡ ✈❛❧✉❡s ♦❢ t❤❡ ♣❛r❛♠❡t❡r

D0✳ ❚❤❡ ✐♥❝r❡❛s❡s ♦❢ D0 ✐♥❝r❡❛s❡s t❤❡ s✐③❡ ♦❢ t❤❡ ❝♦❧♦♥② ❛♥❞ r❡❞✉❝❡❞ ✐t ❛r❡❛❧ ❜✐♦♠❛ss

❞❡♥s✐t② ✭✈❡rt✐❝❛❧ ❛①✐s✮✳ ❚❤❡ s❤❛♣❡ ♦❢ t❤❡ ❝♦❧♦♥② ❤♦✇❡✈❡r st✐❧❧ ❤❛✈❡ t❤❡ st❛r✲❧✐❦❡ s❤❛♣❡

✇✐t❤ ✜♥❣❡rs ❞✐r❡❝t❡❞ t♦✇❛r❞s t❤❡ ❝❧♦s❡st ❜♦✉♥❞❛r②✳

✷✳✼ ❉✐s❝✉ss✐♦♥

■❇▼ ❛♥❞ ❉❘▼ ❛r❡ t✇♦ ❝♦♠♠♦♥❧② ✉s❡❞ ♠♦❞❡❧✐♥❣ ❛♣♣r♦❛❝❤❡s ❢♦r s✐♠✉❧❛t✐♥❣ ♠✐❝r♦✲

❜✐❛❧ s♣❛t✐❛❧ ♣❛tt❡r♥s ❢♦r♠❛t✐♦♥✳ ■♥ t❤✐s ❝❤❛♣t❡r ✇❡ ❝♦♠♣❛r❡❞ t❤❡s❡ t✇♦ ❛♣♣r♦❛❝❤❡s

❜② ❝♦♥s✐❞❡r✐♥❣ ❛ s✐♠♣❧❡ ❝❛s❡ ♦❢ t❤❡ ❛ ♠♦♥♦✲s♣❡❝✐❡s ❝♦❧♦♥② ❣r♦✇✐♥❣ ♦♥ ❛ ❞✐✛✉s✐✈❡ s✉❜✲

str❛t❡✳ ❇♦t❤ ♠♦❞❡❧s ②✐❡❧❞ ❝♦♠♣❛r❛❜❧❡ r❡s✉❧ts ❢♦r t❤❡ ❝❛s❡ ♦❢ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡

❜✉t s❤♦✇ s✐❣♥✐✜❝❛♥t ❞✐✛❡r❡♥❝❡s ✐♥ t❤❡ ❝❛s❡ ♦❢ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡✳ ❲❤✐❧❡ ✱ ✐♥t

❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡ ❡❛❝❤ r❡❛❧✐③❛t✐♦♥ ♦❢ t❤❡ ■❇▼ ②✐❡❧❞s ❛ ♣❛tt❡r♥ ✇✐t❤ ❛♥

✐rr❡❣✉❧❛r s❤❛♣❡ ❛♥❞ ✬✜♥❣❡r✲❧✐❦❡✬ str✉❝t✉r❡ t❤❡ ❛✈❡r❛❣❡ ♣❛tt❡r♥ ②✐❡❧❞s ❛ r♦✉♥❞ s❤❛♣❡❞

❝♦❧♦♥② s✉❣❣❡st✐♥❣ t❤❡ ✬✜♥❣❡rs✬ ❤❛✈❡ ♥♦ ♣r❡❢❡r❡♥t✐❛❧ ❞✐r❡❝t✐♦♥✳ ❚❤❡ ❞✐r❡❝t ❛✈❡r❛❣✐♥❣

♦❢ s♣❛t✐❛❧ ♣❛tt❡r♥s ♦❜t❛✐♥❡❞ t❤r♦✉❣❤ t❤❡ r❡♣❧✐❝❛t✐♦♥ ♦❢ ❛ s✐♠✉❧❛t✐♦♥ ✐s ♦❢t❡♥ ❛♥ ✐♥✲

❛♣♣r♦♣r✐❛t❡ ❛♣♣r♦❛❝❤ ❛s s♦♠❡ ✐♠♣♦rt❛♥t ❢❡❛t✉r❡s ♦❢ t❤❡ ♣❛tt❡r♥ ✭✐rr❡❣✉❧❛r s❤❛♣❡✱

✜♥❣❡r ❢♦r♠❛t✐♦♥✮ t❤❛t ❤❛s ❛♥ ✐♠♣❛❝t ♦♥ t❤❡ ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛r❡

❧♦st ❞✉r✐♥❣ t❤❡ ❛✈❡r❛❣✐♥❣ ❡①❡r❝✐s❡✳

❚❤❡ ❉❘▼ ❝❛♣t✉r❡s t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ✬✜♥❣❡rs✬ ✐♥ t❤❡ ❝❛s❡ ♦❢ t❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬

r❡❣✐♠❡✳ ❚❤❡ ❉❘▼ ♣❛tt❡r♥ ✐s s②♠♠❡tr✐❝ ❛♥❞ t❤❡ ✜♥❣❡rs ❞✐r❡❝t❡❞ t♦✇❛r❞s t❤❡ ❝❧♦s❡st

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✷✹

❈❤❛♣t❡r ✷✳ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

✭❛✮ ■❇▼ time = 0 ✭❜✮ ❉❘ time = 0

✭❝✮ ■❇▼ time = 10h ✭❞✮ ❉❘ time = 10h

✭❡✮ ■❇▼ time = 20h ✭❢✮ ❉❘ time = 20h

❋✐❣✉r❡ ✷✳✹✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ♣❛tt❡r♥ s✐♠✉❧❛t❡❞ ❜② t❤❡ ■❇▼ ❛♥❞ ❜② t❤❡

❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ✐♥ t❤❡ ❝❛s❡ ♦❢ ❛ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞ r❡❣✐♠❡✬✳ ❉❘▼ s✐♠✉❧❛t✐♦♥

❝♦♥❞✉❝t❡❞ ✇✐t❤ D0 = 10−14 m2/s

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✷✳✼✳ ❉✐s❝✉ss✐♦♥ ✷✺

✭❛✮ ■❇▼ time = 0 ✭❜✮ ❉❘ time = 0

✭❝✮ ■❇▼ time = 50h ✭❞✮ ❉❘ time = 50h

✭❡✮ ■❇▼ time = 100h ✭❢✮ ❉❘ time = 100h

❋✐❣✉r❡ ✷✳✺✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ♣❛tt❡r♥ s✐♠✉❧❛t❡❞ ❜② t❤❡ ■❇▼ ❛♥❞ ❜② t❤❡

❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ✐♥ t❤❡ ❝❛s❡ ♦❢ ❛ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞ r❡❣✐♠❡✬✳ ❉❘▼ s✐♠✉❧❛t✐♦♥

❝♦♥❞✉❝t❡❞ ✇✐t❤ D0 = 10−16 m2/s

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✷✻

❈❤❛♣t❡r ✷✳ ▼✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✿ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧

✭❛✮ ■❇▼ time = 71h ✭❜✮ ❉❘ time = 71h✱ D0 = 10−14

✭❝✮ ❉❘ time = 71h✱ D0 = 10−15 ✭❞✮ ❉❘ time = 71h✱ D0 = 10

−16

❋✐❣✉r❡ ✷✳✻✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ❛✈❡r❛❣❡ ♣❛tt❡r♥ ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ✭❛✮ ❛♥❞ t❤❡

♣❛tt❡r♥ s✐♠✉❧❛t❡❞ ✇✐t❤ ❉❘▼ ✭❜✮✲✭❞✮ ❢♦r ❞✐✛❡r❡♥t ✈❛❧✉❡s ♦❢ D0

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✷✳✼✳ ❉✐s❝✉ss✐♦♥ ✷✼

❜♦✉♥❞❛r②✳ ❖♥❡ ♦❢ t❤❡ ❧✐♠✐t❛t✐♦♥s ♦❢ t❤❡ ❉❘▼s ✐s t❤❡ ✐❞❡♥t✐✜❛❜✐❧✐t② ♦❢ t❤❡ ♠♦❞❡❧

♣❛r❛♠❡t❡rs✳ ❆s t❤❡s❡ ♠♦❞❡❧s ❛r❡ r❛r❡❧② r✐❣♦r♦✉s❧② ❞❡r✐✈❡❞ ❢r♦♠ t❤❡ ♠✐❝r♦s❝❛❧❡ ❞②✲

♥❛♠✐❝ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s t❤❡② ✐♠♣❧② t❤❡ ✉s❡ ♦❢ ❛❞✲❤♦❝ ❛♣♣r♦①✐♠❛t✐♦♥s ✐♥✈♦❧✈✐♥❣

s❡✈❡r❛❧ ♣❛r❛♠❡t❡rs✳ ❚❤❡s❡ ♣❛r❛♠❡t❡rs ❡♥❝♦♠♣❛ss t❤❡ ❝♦♠♣❧❡①✐t② ♦❢ t❤❡ ♠✐❝r♦s❝❛❧❡

✐♥t❡r❛❝t✐♦♥ ❛♥❞ ♠❛② ❧❛❝❦ ♣❤②s✐❝❛❧ ♠❡❛♥✐♥❣✳ ❚❤✉s t❤❡✐r ✈❛❧✉❡s ♠❛② ❜❡ ❞✐✣❝✉❧t t♦

♦❜t❛✐♥ ❢r♦♠ ❧❛❜♦r❛t♦r② ❡①♣❡r✐♠❡♥ts✳

❆♣♣❧②✐♥❣ ❜♦t❤ ❛♣♣r♦❛❝❤❡s t♦ ❛ s❛♠❡ ♣r♦❜❧❡♠ ♠❛② ❜❡ ✈❡r② ❤❡❧♣❢✉❧✳ ❉❘▼ ♣r♦✈✐❞❡

❛ ❞❡t❡r♠✐♥✐st✐❝ r❡❢❡r❡♥❝❡ t♦ ✇❤✐❝❤ t❤❡ ■❇▼ s✐♠✉❧❛t✐♦♥s ❝❛♥ ❜❡ ❝♦♠♣❛r❡❞ ✇❤✐❧❡ t❤❡

■❇▼ ♠❛② ❤❡❧♣ ✐♥ ❛ss❡ss✐♥❣ t❤❡ q✉❛❧✐t② ♦❢ t❤❡ ❛♣♣r♦①✐♠❛t✐♦♥s ♥❡❡❞❡❞ ✐♥ t❤❡ ❉❘▼

❛♥❞ ✐♥ t❤❡ ✐❞❡♥t✐✜❛❜✐❧✐t② ♦❢ t❤❡ ❉❘▼ ♣❛r❛♠❡t❡rs✳

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Page 42: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❈❤❛♣t❡r ✸

▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛

♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥② ❣r♦✇t❤

❈♦♥t❡♥ts

✸✳✶ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✸✵

✸✳✶✳✶ ❖✈❡r✈✐❡✇ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✵

✸✳✶✳✷ ❉❡s✐❣♥ ❝♦♥❝❡♣ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✶

✸✳✶✳✸ ❉❡t❛✐❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✷

✸✳✶✳✹ P❛r❛♠❡t❡rs ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✷

✸✳✶✳✺ ▼♦❞❡❧ ♦✉t♣✉ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✸

✸✳✶✳✻ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✇✐t❤ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ ✳ ✳ ✸✸

✸✳✶✳✼ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✸✹

✸✳✶✳✽ ❙♦❧✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✸

✸✳✷ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✇✐t❤ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✹✺

✸✳✷✳✶ ❉❡♥s✐t② ✐♥❞❡♣❡♥❞❡♥t ❣r♦✇t❤ ♠♦❞❡❧ ✭b′1= 0✮ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✺

✸✳✷✳✷ ❉❡♥s✐t② ❞❡♣❡♥❞❛♥t ❞✐✈✐s✐♦♥ ♠♦❞❡❧ ✭b′1> 0✮ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✽

✸✳✸ ❉✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✹✾

✸✳✹ ❆♥♥❡①❡ ❆✿ ❡①♣r❡ss✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✐♥ r❛❞✐❛❧ ❝♦♦r❞✐✲

♥❛t❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✷

■♥ t❤❡ ♣r❡✈✐♦✉s ❝❤❛♣t❡r ✭❝❤❛♣t❡r ✷✮ ✇❡ ✐♥✈❡st✐❣❛t❡❞ ❤♦✇ ❛ s♣❛t✐❛❧❧② ❡①♣❧✐❝✐t

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❢♦r s✐♠✉❧❛t✐♥❣ t❤❡ ❣r♦✇t❤ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❝♦♠♣❛r❡s

t♦ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧s✳ ■♥ t❤✐s ❝❤❛♣t❡r ✇❡ ❛r❡ ❝♦♥❝❡r♥❡❞ ✇✐t❤ ❛♥♦t❤❡r ❝❧❛ss

♦❢ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s✱ ♥❛♠❡❧② s♣❛t✐❛❧ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧s✳

❙♣❛t✐❛❧ ♠♦♠❡♥ts ♠♦❞❡❧s ✇❡r❡ ♦r✐❣✐♥❛❧❧② ❞❡✈❡❧♦♣❡❞ ✐♥ st❛t✐st✐❝❛❧ ♣❤②s✐❝s ❛♥❞ ❤❛✈❡

❜❡❡♥ ❛♣♣❧✐❡❞ ❞✉r✐♥❣ t❤❡ ❧❛st ❞❡❝❛❞❡ t♦ t❤❡ ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧s

t❤❛t ❛r✐s❡ ✐♥ s❡✈❡r❛❧ ❡❝♦❧♦❣✐❝❛❧ s②st❡♠s ♦❢ ♣❧❛♥ts ❛♥❞ ❛♥✐♠❛❧s ❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪✳ ■♥

t❤✐s ❝❤❛♣t❡r ✇❡ ❞✐s❝✉ss t❤❡ ❡①t❡♥s✐♦♥ ♦❢ t❤❡ ❛♣♣r♦❛❝❤ t♦ ♠♦❞❡❧✐♥❣ ♠✐❝r♦❜✐❛❧ s②st❡♠s

❛♥❞ ✐❧❧✉str❛t❡ ✇✐t❤ t❤❡ ❡①❛♠♣❧❡ ♦❢ ♠✐❝r♦❜✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤ ✇✐t❤ ❛ s❧✐❣❤t ❞✐✛❡r❡♥❝❡

❝♦♠♣❛r❡❞ t♦ t❤❡ ♣r❡✈✐♦✉s ❝❤❛♣t❡r✳ ❍❡r❡ ✇❡ ✇✐❧❧ ❝♦♥s✐❞❡r s②st❡♠s ✐♥✐t✐❛❧✐③❡❞ ✇✐t❤

n0 > 1 ✐♥❞✐✈✐❞✉❛❧s r❛♥❞♦♠❧② ❞✐str✐❜✉t❡❞ r❛t❤❡r t❤❛♥ ✇✐t❤ ♦♥❡ ✐♥❞✐✈✐❞✉❛❧ ❧♦❝❛t❡❞ ✐♥

t❤❡ ❝❡♥t❡r ♦❢ t❤❡ ❞♦♠❛✐♥✳

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✸✵

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

❚❤❡ ❞❡r✐✈❛t✐♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♥❣ ♠♦❞❡❧ ❢r♦♠ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ ✐♥✲

❝❧✉❞✐♥❣ ✐♥❞✐✈✐❞✉❛❧s ✇✐t❤ ✈❛r✐❛❜❧❡ s✐③❡s ❛♥❞ ❝♦♠♣❧❡① s❤♦✈✐♥❣ ♣r♦❝❡ss ✐s q✉✐❡t ❞✐✣❝✉❧t✳

❚❤✉s ♦✉r ❛♣♣r♦❛❝❤ ❝♦♥s✐st ✐♥ ✜rst s✐♠♣❧✐❢②✐♥❣ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ t❤❛♥ ❛♣♣r♦①✐♠❛t❡

t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✉s✐♥❣ ♠♦♠❡♥t t❡❝❤♥✐q✉❡s✳

❚❤❡ ❝❤❛♣t❡r ✐♥ ♦r❣❛♥✐③❡❞ ✐♥ t❤r❡❡ ♣❛rts✿ t❤❡ ✜rst ♣❛rt ✐s ❞❡❞✐❝❛t❡❞ t♦ t❤❡ s✐♠✲

♣❧✐✜❝❛t✐♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ❣r♦✇t❤ ■❇▼✳ ■♥ t❤❡ s❡❝♦♥❞ ♣❛rt ✇❡ ❞❡r✐✈❡ ❛ ♠♦♠❡♥t ❛♣✲

♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼✳ ■♥ t❤❡ t❤✐r❞ ♣❛rt ✇❡ ❝♦♠♣❛r❡ t❤❡ ♠♦♠❡♥t

♠♦❞❡❧ ❛♥❞ t❤❡ s✐♠♣❧✐✜❡❞ ♠♦❞❡❧ t♦ ❛ss❡ss t❤❡ q✉❛❧✐t② ♦❢ t❤❡ ❛♣♣r♦①✐♠❛t✐♦♥s ❝♦♥s✐❞✲

❡r❡❞ ✐♥ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❲❡ ❝♦♥❝❧✉❞❡ t❤✐s ❝❤❛♣t❡r ❜② ❞✐s❝✉ss✐♥❣ t❤❡ r❡❧❡✈❛♥❝❡

♦❢ t❤❡ s♣❛t✐❛❧ ♠♦♠❡♥t ♠❡t❤♦❞ ✐♥ ❛♣♣r♦①✐♠❛t✐♥❣ ♠✐❝r♦❜✐❛❧ ■❇▼s ❛♥❞ t❤❡ ♣♦ss✐❜❧❡

❡①t❡♥s✐♦♥s ♦❢ t❤❡ ❛♣♣r♦❛❝❤✳

✸✳✶ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

❲❡ ❞❡s❝r✐❜❡ ✐♥ ❈❤❛♣t❡r ✷ ❛♥ ■❇▼ ❢♦r t❤❡ ❣r♦✇t❤ ♦❢ ❛ ❝♦❧♦♥② ✐♥ ✇❤✐❝❤ t❤❡ ✐♥✲

❞✐✈✐❞✉❛❧ ❝❡❧❧s ❛r❡ r❡♣r❡s❡♥t❡❞ ❛s ❞✐s❝s ✇✐t❤ ✈❛r✐❛❜❧❡ ❞✐❛♠❡t❡rs✳ ❚❤❡ ✐♥❞✐✈✐❞✉❛❧s

❣r♦✇ ❛♥❞ ❞✐✈✐❞❡ ✇❤✐❧❡ ✉♣t❛❦✐♥❣ ❛ ❞✐✛✉s✐✈❡ s✉❜str❛t❡✳ ❚❤❡② s❤♦✈❡ ❡❛❝❤ ♦t❤❡rs ♠❛❦✲

✐♥❣ t❤❡ s✐③❡ ♦❢ t❤❡ ❝♦❧♦♥② t♦ ✐♥❝r❡❛s❡✳ ❚❤❡ ✐♥❞✐✈✐❞✉❛❧s ❝♦♠♣❡t❡ ❢♦r t❤❡ ♥✉tr✐❡♥t

❛♥❞ t❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡✐r ❧♦❝❛❧ ❞❡♥s✐t② ❞❡❝r❡❛s❡s t❤❡ ❧❡✈❡❧ ♦❢ ♥✉tr✐❡♥t ❛♥❞ r❡❞✉❝❡s

t❤❡✐r ❣r♦✇t❤ r❛t❡✳ ❚❤✐s ♣❤❡♥♦♠❡♥❛ ✐s s♦♠❡❤♦✇ ❝♦♠♣❛r❛❜❧❡ t♦ ❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

❣r♦✇t❤ ♣r♦❝❡ss✳ ❲❤❡♥ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ t❤❡ ❜❛❝t❡r✐❛ ✐♥❝r❡❛s❡s t❤❡✐r ✐♥❞✐✈✐❞✉❛❧

❣r♦✇t❤ r❛t❡ ❞❡❝r❡❛s❡s ❜❡❝❛✉s❡ ♦❢ t❤❡ ❞❡❝r❡❛s❡ ♦❢ t❤❡ ❧♦❝❛❧ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥

♣❡r❝❡✐✈❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛✳ ❲❡ ♣r♦♣♦s❡ t♦ ❝♦♥str✉❝t ❛ s✐♠♣❧❡ ■❇▼ t❤❛t ❝❛♣t✉r❡s

t❤✐s ❞❡♥s✐t②✲❞❡♣❡♥❞❛♥t ❣r♦✇t❤ ✇✐t❤♦✉t ❝♦♥s✐❞❡r✐♥❣ t❤❡ ✈❛r✐❛❜✐❧✐t② ✐♥ ✐♥❞✐✈✐❞✉❛❧ s✐③❡

❛♥❞ t❤❡ ❡①♣❧✐❝✐t ❞②♥❛♠✐❝ ♦❢ t❤❡ s✉❜str❛t❡✳ ❲❡ ❛❧s♦ s✐♠♣❧✐❢② t❤❡ s❤♦✈✐♥❣ ♣r♦❝❡ss ❜②

✉s✐♥❣ ✐♥st❡❛❞ ❛ ✉♥✐❢♦r♠ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧✳ ❲❡ ❛ss❡ss ❤♦✇ t❤✐s s✐♠♣❧✐✜❝❛t✐♦♥ ❛✛❡❝t

t❤❡ s❤❛♣❡ ♦❢ t❤❡ ❝♦❧♦♥②✳ ■♥ t❤✐s s❡❝t✐♦♥ ✇❡ ♣r♦♣♦s❡ t♦ ❞❡s❝r✐❜❡ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼

✉s✐♥❣ t❤❡ ❖❉❉ ♣r♦t♦❝♦❧✳

✸✳✶✳✶ ❖✈❡r✈✐❡✇

✸✳✶✳✶✳✶ ❙t❛t❡ ✈❛r✐❛❜❧❡s ❛♥❞ s❝❛❧❡s

❲❡ ❝♦♥s✐❞❡r ❛ s❡ss✐❧❡ ❝♦♠♠✉♥✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧ ❜❛❝t❡r✐❛❧ ❝❡❧❧s ❧✐✈✐♥❣ ✐♥ ❛ t✇♦✲

❞✐♠❡♥s✐♦♥❛❧ s♣❛❝❡✳ ❚❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❛r❡ ❝♦♥s✐❞❡r❡❞ ❛s ♣♦✐♥t ♣❛rt✐❝❧❡s ❡♥t✐r❡❧②

❝❤❛r❛❝t❡r✐③❡❞ ❜② t❤❡✐r ❧♦❝❛t✐♦♥ x = (x1, x2) ✐♥ t❤✐s ♣❧❛♥❡✳ ❚❤❡ ❛❜✐♦t✐❝ ❡♥✈✐r♦♥♠❡♥t

✐s ❤♦♠♦❣❡♥❡♦✉s ✐♥ s♣❛❝❡✳

✸✳✶✳✶✳✷ Pr♦❝❡ss ♦✈❡r✈✐❡✇

❚❤❡ ❝♦♠♠✉♥✐t② ❝❤❛♥❣❡s t❤r♦✉❣❤ t✇♦ st♦❝❤❛st✐❝ ❡✈❡♥ts ❛❝t✐♥❣ ♦♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✿

❞✐✈✐s✐♦♥ ❛♥❞ ❧②s✐s ✭♦r ❞❡❛t❤✮✳ ❲❡ s✉♣♣♦s❡ t❤❛t ✐♥❞✐✈✐❞✉❛❧s ❞✐✈✐❞❡ ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t②

t❤❛t ❞❡❝r❡❛s❡s ✇✐t❤ t❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ ❞✐❡ ✇✐t❤

❛ ❝♦♥st❛♥t ♣r♦❜❛❜✐❧✐t②✳ ❚❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ✐s ♠❡❛s✉r❡❞ ✉s✐♥❣ ❛♥ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧

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✸✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✸✶

s♣❡❝✐❢②✐♥❣ ❤♦✇ ♥❡✐❣❤❜♦r✐♥❣ ✐♥❞✐✈✐❞✉❛❧s ❛✛❡❝t t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ ❛ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧✳

❉✉r✐♥❣ ❛ ❞✐✈✐s✐♦♥ ❡✈❡♥t ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡ ♣❛r❡♥t ✐♥❞✐✈✐❞✉❛❧ ❣❡♥❡r❛t❡s ❛♥ ♦✛s♣r✐♥❣

✇❤✐❝❤ ♣♦s✐t✐♦♥ ✐s r❛♥❞♦♠❧② s❡❧❡❝t❡❞ ✇✐t❤✐♥ ❛ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ ✐ts ♣❛r❡♥t✳

✸✳✶✳✶✳✸ ❙❝❤❡❞✉❧✐♥❣

❚❤❡ t❡♠♣♦r❛❧ ❜❡❤❛✈✐♦r ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✐s ❣♦✈❡r♥❡❞ s♦❧❡❧② ❜② t❤❡ st♦❝❤❛s✲

t✐❝ ❞✐✈✐s✐♦♥ ❛♥❞ ❞❡❛t❤ ❡✈❡♥ts✳ ❚♦ s✐♠✉❧❛t❡ t❤❡ t❡♠♣♦r❛❧ ❡✈♦❧✉t✐♦♥ ♦❢ s✉❝❤ s②st❡♠

✇❡ ♥❡❡❞ t♦ s♣❡❝✐❢② ✇❤❡♥ t❤❡ ♥❡①t ❡✈❡♥t ✇✐❧❧ ♦❝❝✉r✱ ✇❤❛t ❦✐♥❞ ♦❢ ❡✈❡♥t ✐t ✇✐❧❧ ❜❡

❛♥❞ ✇❤✐❝❤ ✐♥❞✐✈✐❞✉❛❧ ✇✐❧❧ ❜❡ ❝♦♥❝❡r♥❡❞ ✇✐t❤ t❤❡ ❡✈❡♥t✳ ●✐❧❧❡s♣✐❡ ❬●■❧❧❡s♣✐❡ ✶✾✼✻❪

♣r♦♣♦s❡❞ ❛ ▼♦♥t❡ ❈❛r❧♦ ♣r♦❝❡❞✉r❡ ❢♦r s✐♠✉❧❛t✐♥❣ ❝♦♠♣❛r❛❜❧❡ st♦❝❤❛st✐❝ ♣r♦❝❡ss❡s

t❤❛t ❛r✐s❡ ✐♥ ❝❤❡♠✐❝❛❧ r❡❛❝t✐♦♥ r❡s❡❛r❝❤✳ ❚❤❡ ♣r♦❝❡❞✉r❡ ❝❛♥ ❡❛s✐❧② ❜❡ ❡①t❡♥❞❡❞ t♦

❛ st♦❝❤❛st✐❝ ❜✐rt❤✲❞❡❛t❤ ♠♦❞❡❧ ✐♥ ✇❤✐❝❤ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❡①♣❡r✐❡♥❝❡ ❞✐✛❡r❡♥t ❜✐rt❤

❛♥❞ ❞❡❛t❤ ♣r♦❜❛❜✐❧✐t✐❡s ❬❉✐❡❝❦♠❛♥♥ ✶✾✾✾❪✳ ❚❤❡ ♣r♦❝❡❞✉r❡ ✐t❡r❛t❡ ♦✈❡r t❤❡ ❢♦❧❧♦✇✐♥❣

st❡♣s✿

✶✳ ❙❡t t❤❡ t✐♠❡ t♦ t = 0

✷✳ ❈❛❧❝✉❧❛t❡ t❤❡ ❞✐✈✐s✐♦♥ ❛♥❞ ❞❡❛t❤ r❛t❡s bi(p) ❛♥❞ di ♦❢ ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧ i = 1..n

✇❤❡r❡ p ✐s t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❛t t✐♠❡ t

✸✳ ❈❛❧❝✉❧❛t❡ t❤❡ s✉♠s rb =∑n

i=1bi(p) ❛♥❞ rd =

∑ni=1

di✳ ❚❤❡ r❛t❡ ❛t ✇❤✐❝❤ ❛♥

❡✈❡♥t ✭❞✐✈✐s✐♦♥ ♦r ❞❡❛t❤✮ ♦❝❝✉rs ✐s ❣✐✈❡♥ ❜② r(t) = rb(t) + rd(t)

✹✳ ❈❤♦♦s❡ t❤❡ ✇❛✐t✐♥❣ t✐♠❡ τ ❢♦r t❤❡ ♥❡①t ❡✈❡♥t t♦ ♦❝❝✉r ❛❝❝♦r❞✐♥❣ t♦ τ = −1

r lnλ

✇❤❡r❡ 0 < λ ≤ 1 ✐s ❛ ✉♥✐❢♦r♠❧② ❞✐str✐❜✉t❡❞ r❛♥❞♦♠ ♥✉♠❜❡r

✺✳ ❈❤♦♦s❡ ❛ ❞✐✈✐s✐♦♥ ♦r ❞❡❛t❤ ❡✈❡♥t ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② rb/r ❛♥❞ rd/r r❡s♣❡❝t✐✈❡❧②

✻✳ ❈❤♦♦s❡ ❛♥ ✐♥❞✐✈✐❞✉❛❧ k ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② bk/rb ✭✐❢ t❤❡ ❡✈❡♥t ✐s ❞✐✈✐s✐♦♥✮ ♦r

dk/rd ✐❢ t❤❡ ❡✈❡♥t ✐s ❞❡❛t❤✱ ✇❤❡r❡ bk ❛♥❞ dk ❛r❡ t❤❡ r❡s♣❡❝t✐✈❡❧② t❤❡ ❞✐✈✐s✐♦♥

❛♥❞ ❞❡❛t❤ r❛t❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ k

✼✳ P❡r❢♦r♠ t❤❡ s❡❧❡❝t❡❞ ❡✈❡♥t ♦♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧ k

✽✳ ❯♣❞❛t❡ t✐♠❡ ❛❝❝♦r❞✐♥❣ t♦ t = t+ τ

✾✳ ❈♦♥t✐♥✉❡ ❢r♦♠ st❡♣ ✷ ✉♥t✐❧ t < tend

✸✳✶✳✷ ❉❡s✐❣♥ ❝♦♥❝❡♣ts

• ❙t♦❝❤❛st✐❝✐t②✿ ❛❧❧ t❤❡ ♣r♦❝❡ss❡s ✭❞✐✈✐s✐♦♥ ❛♥❞ ❞❡❛t❤ ♣r♦❝❡ss❡s✮❛r❡ st♦❝❤❛st✐❝✳

• ❊♠❡r❣❡♥❝❡✿ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❡♠❡r❣❡s ❢r♦♠ t❤❡ ✐t❡r❛t✐♦♥ ♦❢ ❞✐✈✐s✐♦♥ ❛♥❞

❞❡❛t❤ ♣r♦❝❡ss❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳

Page 45: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✸✷

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

✸✳✶✳✸ ❉❡t❛✐❧s

✸✳✶✳✸✳✶ ■♥✐t✐❛❧✐③❛t✐♦♥

❚❤❡ ♠♦❞❡❧ ✐s ✐♥✐t✐❛❧✐③❡❞ ✇✐t❤ N0 = 100 ❝❡❧❧s ❞✐str✐❜✉t❡❞ ✉♥✐❢♦r♠❧② ♦✈❡r t❤❡ ❞♦♠❛✐♥✳

✸✳✶✳✸✳✷ ❙✉❜♠♦❞❡❧s

• ❉✐✈✐s✐♦♥✿ ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡ t❤❛t ❛♥ ✐♥❞✐✈✐❞✉❛❧

i ✐♥ ♣♦s✐t✐♦♥ xi ♣r♦❞✉❝❡s ❛ ♥❡✇ ❝❡❧❧ ❧♦❝❛t❡❞ ✐♥ ♣♦s✐t✐♦♥ x′ ✐s ❣✐✈❡♥ ❜②✿

B(xi, x′) = [b1 − b′1ploc(xi)]K

(

||xi − x′||

wb

)

✭✸✳✶✮

❚❤❡ ♣❛r❛♠❡t❡rs b1 ❛♥❞ b′1 ❛r❡ t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❛♥❞ t❤❡ ❞❡♥s✐t②✲

❞❡♣❡♥❞❛♥t ❞✐✈✐s✐♦♥ r❛t❡s r❡s♣❡❝t✐✈❡❧②✳ ❚❤❡ t❡r♠ ploc(xi) ✐s t❤❡ ❧♦❝❛❧ ❞❡♥✲

s✐t② ✭❞❡✜♥❡❞ ✐♥ ♠♦r❡ ❞❡t❛✐❧s ❜❡❧♦✇✮ ♣❡r❝❡✐✈❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ xi✳

K(||xi−x′||/wb) ✐s ❛ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧ ✭✇❡ ❝❛❧❧ ✐t ❛❧s♦ ❜✐rt❤ ♦r ❞✐✈✐s✐♦♥ ❦❡r♥❡❧✮✳

❚❤❡ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧ ❣✐✈❡s t❤❡ ♣r♦❜❛❜✐❧✐t② t❤❛t t❤❡ ♥❡✇❧② ❢♦r♠❡❞ ✐♥❞✐✈✐❞✲

✉❛❧ ❞✐s♣❡rs❡s ✐♥st❛♥t❛♥❡♦✉s❧② ❛❢t❡r t❤❡ ❞✐✈✐s✐♦♥ ❡✈❡♥t t♦ t❤❡ ❧♦❝❛t✐♦♥ x′✳ ❋♦r

s✐♠♣❧✐❝✐t② ✇❡ ✉s❡ ❛ ✉♥✐❢♦r♠ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧✳ ■♥ s♦♠❡ ✇❛②✱ t❤❡ ❞✐s♣❡rs✐♦♥

❦❡r♥❡❧ tr❛♥s❧❛t❡s t❤❡ ♦❜s❡r✈❛t✐♦♥ t❤❛t ❞❛✉❣❤t❡r ❝❡❧❧s ❛r❡ ❧♦❝❛t❡❞ r❛♥❞♦♠❧② ✐♥

t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡✐r ♠♦t❤❡r ❝❡❧❧s✳

• ❈❛❧❝✉❧❛t✐♦♥ ♦❢ t❤❡ ♣❡r❝❡✐✈❡❞ ❧♦❝❛❧ ❞❡♥s✐t②✿ ✐♥ ❛ s②st❡♠ ❝♦♥t❛✐♥✐♥❣ N ✐♥❞✐✲

✈✐❞✉❛❧s✱ ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧ ❤❛s ❛t ♠❛①✐♠✉♠ N − 1 ♥❡✐❣❤❜♦rs✳ ❍♦✇❡✈❡r✱ ❛s ✇❡

s✉♣♣♦s❡ t❤❛t ✐♥❞✐✈✐❞✉❛❧s ♣❡r❝❡✐✈❡ ♦♥❧② t❤❡✐r ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t✳ ❚❤❡② ❛r❡ ❧✐❦❡❧②

t♦ ❜❡ ❛✛❡❝t❡❞ ♦♥❧② ❜② t❤❡ ♥❡✐❣❤❜♦rs ❧♦❝❛t❡❞ ✐♥ t❤❡✐r ✐♠♠❡❞✐❛t❡ s✉rr♦✉♥❞✐♥❣

❡♥✈✐r♦♥♠❡♥t✳ ■♥ ♦r❞❡r t♦ ❝❛❧❝✉❧❛t❡ t❤✐s ♣❡r❝❡✐✈❡❞ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♥❡✐❣❤❜♦rs ✇❡

✉s❡ ❛ ✉♥✐❢♦r♠ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧✱ ❞❡♥♦t❡❞ K(||xi − xj ||/wd)✳ ❚❤❡ ✐♥t❡r❛❝t✐♦♥

❦❡r♥❡❧ ♠❡❛s✉r❡s t❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ j ✐♥ xj t♦ t❤❡ ❧♦❝❛❧ ❞❡♥✲

s✐t② ♣❡r❝❡✐✈❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ✐♥ xi✳ ❚❤❡ ♣❡r❝❡✐✈❡❞ ❧♦❝❛❧ ❞❡♥s✐t② ✐s t❤❡♥

❝❛❧❝✉❧❛t❡❞ ✉s✐♥❣ t❤❡ ❢♦❧❧♦✇✐♥❣ ❡①♣r❡ss✐♦♥✿

ploc(x) =

j=n∑

j=0,j 6=i

K

(

||xi − xj ||

wd

)

✭✸✳✷✮

• ❉❡❛t❤ ♣r♦❝❡ss✿ ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❞✐❡ ❛t ❛ ❝♦♥st❛♥t r❛t❡ d1✳

❚❤❡ ❞❡❛t❤ ♣r♦❜❛❜✐❧✐t② ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ♣❡r ✉♥✐t ♦❢ t✐♠❡ ✐s s✉♣♣♦s❡❞ t♦ ❜❡

✐♥❞❡♣❡♥❞❡♥t ❢r♦♠ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✳

✸✳✶✳✹ P❛r❛♠❡t❡rs

❚❤❡ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs ❛r❡ s✉♠♠❛r✐③❡❞ ✐♥ t❛❜❧❡ ✶✳

Page 46: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✸✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✸✸

P❛r❛♠❡t❡rs ❉❡s❝r✐♣t✐♦♥ ❱❛❧✉❡ ❯♥✐t

▲ ❙✐❞❡ ♦❢ t❤❡ sq✉❛r❡❞ s♣❛t✐❛❧ ❞♦♠❛✐♥ 101① 101 µm× µm

b1 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ r❛t❡ 0.1 h−1

b′1 ❉❡♥s✐t②✲❞❡♣❡♥❞❛♥t ❞✐✈✐s✐♦♥ r❛t❡ variable h−1µm2/#

d1 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡ 0.1 h−1

wb ❙✐❞❡ ♦❢ t❤❡ ✉♥✐❢♦r♠ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧ 5 µm

wd ❙✐❞❡ ♦❢ t❤❡ sq✉❛r❡❞ ✉♥✐❢♦r♠ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ 5 µm

❚❛❜❧❡ ✸✳✶✿ ▼♦❞❡❧ ♣❛r❛♠❡t❡rs✳ ✭❚❤❡ # s②♠❜♦❧ ❞❡♥♦t❡s ❢♦r t❤❡ ❞✐♠❡♥s✐♦♥ ♦♥ t❤❡

♥✉♠❜❡r ♦❢ ✐♥❞✐✈✐❞✉❛❧s✮

✸✳✶✳✺ ▼♦❞❡❧ ♦✉t♣✉ts

❚❤❡ ♠♦❞❡❧ ♦✉t♣✉t ✐s ❛ ❧✐st ❝♦♥t❛✐♥✐♥❣ t❤❡ ♣♦s✐t✐♦♥s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡ ❧✐st

❞❡✜♥❡s t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❛♥❞ ❝❤❛♥❣❡s ✇❤❡♥ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❡✈❡♥t ✭❞✐✈✐s✐♦♥ ♦r ❞❡❛t❤✮

♦❝❝✉rs✳ ❲❡ ❛♥❛❧②③❡ t❤❡s❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❜② ♠❡❛s✉r✐♥❣ t✇♦ st❛t✐st✐❝❛❧ q✉❛♥t✐t✐❡s

❞❡✜♥✐♥❣ t❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥ts✿

• t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✱ ❞❡♥♦t❡❞ N(t) ✭♥✉♠❜❡r ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❞✐✲

✈✐❞❡❞ ❜② t❤❡ ❛r❡❛ L2 ♦❢ t❤❡ ❞♦♠❛✐♥✮

• t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❞❡♥s✐t② ❢✉♥❝t✐♦♥ ❞❡♥♦t❡❞ C(ξ, p) ❛♥❞ ❞❡✜♥❡❞ ❛s t❤❡ ❞❡♥s✐t②

♦❢ ♣❛✐rs ♦❢ ✐♥❞✐✈✐❞✉❛❧s s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ = (ξ1, ξ2)✳

✸✳✶✳✻ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✇✐t❤ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼

❲❡ ♣r♦♣♦s❡ t♦ ❛ss❡ss t❤❡ ✐♠♣❛❝t ♦❢ s✐♠♣❧✐❢②✐♥❣ t❤❡ s♣❛t✐❛❧ ❡①t❡♥t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s

♦♥ t❤❡ s❤❛♣❡ ♦❢ t❤❡ s✐♠✉❧❛t❡❞ ❝♦❧♦♥✐❡s✳ ■♥ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ t❤❛t ✇❡ ♣r❡s❡♥t❡❞

♣r❡✈✐♦✉s❧② ✭s❡❡ ❝❤❛♣t❡r ✷✮ ✇❡ r❡♣r❡s❡♥t❡❞ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛s ❞✐s❝s s❤♦✈✐♥❣ ❡❛❝❤ ♦t❤❡rs

❛♥❞ ❤❛✈✐♥❣ ✈❛r✐❛❜❧❡ s✐③❡s✳ ❚❤✐s ✐s s✐♠♣❧✐✜❡❞ ✐♥ t❤❡ ■❇▼ ❞❡s❝r✐❜❡❞ ✐♥ t❤✐s ❝❤❛♣t❡r

❛♥❞ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛r❡ r❡♣r❡s❡♥t❡❞ ❛s ♣❛rt✐❝❧❡s ✇✐t❤♦✉t ❛ s♣❛t✐❛❧ ❡①t❡♥t✳ ❇② t❛❦✐♥❣

t❤✐s s✐♠♣❧✐❢②✐♥❣ ❛ss✉♠♣t✐♦♥ ✇❡ ❛❧s♦ ♥❡❣❧❡❝t t❤❡ ♣r♦❝❡ss❡s ✐♥❞✉❝❡❞ ❜② t❤❡ s♣❛t✐❛❧

❡①t❡♥t ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❧✐❦❡ t❤❡ s❤♦✈✐♥❣ ♣r♦❝❡ss✳ ❈♦♥s❡q✉❡♥t❧② ✐♥ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼

t❤❡ ♦♥❧② ♠❡❝❤❛♥✐s♠ t❤❛t ♠❛❦❡s t❤❡ s✐③❡ ♦❢ t❤❡ ❝♦❧♦♥② t♦ ✐♥❝r❡❛s❡ ✐s t❤❡ ❞✐s♣❡rs✐♦♥ ♦❢

❞❛✉❣❤t❡r ❝❡❧❧s ❛❢t❡r ❞✐✈✐s✐♦♥✳ ❲❡ ♠♦❞❡❧❡❞ t❤✐s ❞✐s♣❡rs✐♦♥ ✉s✐♥❣ ❛ ✉♥✐❢♦r♠ ❞✐s♣❡rs✐♦♥

❦❡r♥❡❧✳

❆♥♦t❤❡r ✐♠♣♦rt❛♥t ❞✐✛❡r❡♥❝❡ ❜❡t✇❡❡♥ t❤❡ s✐♠♣❧✐✜❡❞ ♠♦❞❡❧ ❛♥❞ t❤❡ ❞❡t❛✐❧❡❞ ♦♥❡ ✐s

r❡❧❛t❡❞ t♦ t❤❡ s✉❜str❛t❡ ❛♥❞ t❤❡ ❣r♦✇t❤ ❢✉♥❝t✐♦♥s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ■♥ t❤❡ ❞❡t❛✐❧❡❞

♠♦❞❡❧ ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❣r♦✇ ❜② ✉♣t❛❦✐♥❣ ❛ ♥✉tr✐❡♥t ✇❤✐❝❤ ❞②♥❛♠✐❝s

✐s ❡①♣❧✐❝✐t❧② ❝♦♥s✐❞❡r❡❞ ✐♥ t❤❡ ♠♦❞❡❧ ✭✉s✐♥❣ ❛ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠❛ss ❜❛❧❛♥❝❡✮✳ ❚❤❡

❣r♦✇t❤ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐♥ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ ✐s ❛ ♥♦♥✲❧✐♥❡❛r ❢✉♥❝t✐♦♥ ♦❢ t❤❡

❧♦❝❛❧ ♥✉tr✐❡♥t ❝♦♥❝❡♥tr❛t✐♦♥ ✭▼♦♥♦❞ ❡q✉❛t✐♦♥✮✳ ■♥ t❤❡ s✐♠♣❧✐✜❡❞ ♠♦❞❡❧ ✇❡ ❞♦ ♥♦t

Page 47: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✸✹

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

❛❝❝♦✉♥t ❡①♣❧✐❝✐t❧② ❢♦r t❤❡ ♥✉tr✐❡♥t ❞②♥❛♠✐❝✳ ❚❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐s ❛

❞❡❝r❡❛s✐♥❣ ❧✐♥❡❛r ❢✉♥❝t✐♦♥ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳

❋✐❣✉r❡s ✸✳✶ ❛♥❞ ✸✳✷ s❤♦✇ ❝♦❧♦♥② ♣❛tt❡r♥s s✐♠✉❧❛t❡❞ ✇✐t❤ ❜♦t❤ ♠♦❞❡❧s ✐♥ t❤❡ ❝❛s❡

♦❢ ❛ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ ❛♥❞ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡s✳ ❲❡ s✇✐t❝❤ ❢r♦♠ t❤❡ ✬r❡❛❝t✐♦♥✲

❧✐♠✐t❡❞✬ r❡❣✐♠❡ t♦ t❤❡ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡ ❜② ❞❡❝r❡❛s✐♥❣ t❤❡ ♥✉tr✐❡♥t ❞✐✛✉s✐♦♥

❢❛❝t♦r ✐♥ t❤❡ ❞❡t❛✐❧❡❞ ♠♦❞❡❧ ❛♥❞ ❜② ✐♥❝r❡❛s✐♥❣ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

❣r♦✇t❤ ♣❛r❛♠❡t❡r b′1 ✐♥ t❤❡ s✐♠♣❧✐✜❡❞ ♠♦❞❡❧✳ ❚❤❡ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② ❜♦t❤ ♠♦❞❡❧s

s❤♦✇s s✐♠✐❧❛r✐t✐❡s ❛♥❞ ❞✐✛❡r❡♥❝❡s✳ ❋✐rst t❤❡ s✐♠♣❧✐✜❡❞ ♠♦❞❡❧ r❡♣r♦❞✉❝❡s q✉✐❡t ✇❡❧❧

t❤❡ ❝✐r❝✉❧❛r ❛♥❞ ✐rr❡❣✉❧❛r s❤❛♣❡s ♦❜s❡r✈❡❞ ✐♥ t❤❡ ❞❡t❛✐❧❡❞ ♠♦❞❡❧✳ ❚❤❡ ❞✐str✐❜✉t✐♦♥

♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✇✐t❤✐♥ t❤❡ ❝♦❧♦♥② ❛r❡ ❤♦✇❡✈❡r ❞✐✛❡r❡♥t ✐♥ t❤❡ ♣❛tt❡r♥ ②✐❡❧❞❡❞

❜② ❜♦t❤ ♠♦❞❡❧s✳ ■♥ t❤❡ ♦r✐❣✐♥❛❧ ♠♦❞❡❧ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛r❡ t✐❣❤t❧② ♣❛❝❦❡❞ ✇❤❡r❡ ❛s

✐♥ t❤❡ s✐♠♣❧✐✜❡❞ ♠♦❞❡❧ t❤❡② ❛r❡ ❞✐s♣❡rs❡❞ ✇✐t❤✐♥ t❤❡ ❝♦❧♦♥②✳ ❚❤✐s ✐s ❞✉❡ t♦ t❤❡

s✐♠♣❧✐✜❝❛t✐♦♥ ♦❢ t❤❡ ♠❡❝❤❛♥✐❝❛❧ ♣✉s❤✐♥❣ ♣r♦❝❡ss ✭s❤♦✈✐♥❣ ♣r♦❝❡ss✮ ❝♦♥s✐❞❡r❡❞ ✐♥ t❤❡

❞❡t❛✐❧❡❞ ♠♦❞❡❧✳ ❙❤♦✈✐♥❣ ♣r♦❝❡ss r❡❛rr❛♥❣❡s t❤❡ ♣♦s✐t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ t❤❡

❝♦❧♦♥② s✐♠✉❧❛t❡❞ ✇✐t❤ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ ❛♥❞ r❡❧❛① ♦✈❡r❧❛♣♣✐♥❣ ♦❢ ♥❡✐❣❤❜♦r✐♥❣ ❝❡❧❧s✳

■♥ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ t❤❡ ❝❡❧❧s ❝♦♥t✐♥✉♦✉s❧② s❤♦✈❡ ❡❛❝❤ ♦t❤❡rs ❛♥❞ t❤❡✐r ♣♦s✐t✐♦♥ ✐♥

s❧✐❣❤t❧② ♠♦❞✐✜❡❞ ❛❢t❡r ❡❛❝❤ t✐♠❡ st❡♣ ✇❤✐❧❡ ✐♥ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ t❤❡ ♣♦s✐t✐♦♥ ♦❢ t❤❡

❞❛✉❣❤t❡r ❝❡❧❧ ✐s ✜①❡❞ ❛❢t❡r t❤❡ ❞✐✈✐s✐♦♥ ❡✈❡♥t ❛♥❞ ❞♦ ♥♦t ❝❤❛♥❣❡ ✐♥ t✐♠❡✳ ❚❤❡ ❡✛❡❝t

♦❢ s❤♦✈✐♥❣ ❝❛♥ ❜❡ ✐♥❝❧✉❞❡❞ ✐♥ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ❜② ❛❞❞✐♥❣ ❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

♠♦t✐❧✐t② ♣r♦❝❡ss ✇❤❡r❡ ✐♥❞✐✈✐❞✉❛❧s ❜❡❝♦♠❡ ♠♦t✐❧❡ ✇❤❡♥ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♥❡✐❣❤❜♦rs

✐♥❝r❡❛s❡s✳ ❍♦✇❡✈❡r ❢♦r s✐♠♣❧✐❝✐t② ✇❡ ❞♦ ♥♦t ✐♥❝❧✉❞❡ t❤✐s ❡✛❡❝t ❛♥❞ ❝♦♥s✐❞❡r t❤❛t t❤❡

s✐♠♣❧✐✜❡❞ ■❇▼ ❛❧r❡❛❞② ❝❛♣t✉r❡s t❤❡ ♠❛✐♥ ❢❡❛t✉r❡s ♦❢ ❝♦❧♦♥② s❤❛♣❡✳ ❆♥♦t❤❡r ❢♦r♠

♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② ✇✐❧❧ ❜❡ st✉❞✐❡❞ ✐♥ ♠♦r❡ ❞❡t❛✐❧ ✐♥ ❝❤❛♣t❡r ✺ t♦ ✼✳

❋✐♥❛❧❧②✱ s✉❜str❛t❡ ❞②♥❛♠✐❝ ❝❛♥ ❛❧s♦ ❜❡ ✐♥❝❧✉❞❡❞ ✐♥ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ❜② r❡♣r❡✲

s❡♥t✐♥❣ s✉❜str❛t❡ ❛s ♣❛rt✐❝❧❡s ✉♥❞❡r❣♦✐♥❣ ❛ ❇r♦✇♥✐❛♥ ♠♦t✐♦♥✳ ❚❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢

t❤❡ ❜❛❝t❡r✐❛ ❝❛♥ ❜❡ ❡①♣r❡ss❡❞ ❛s ❛ ❢✉♥❝t✐♦♥ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ s✉❜str❛t❡ ♣❛r✲

t✐❝❧❡s✱ ❛♥❞ s✉❜str❛t❡ ❝♦♥s✉♠♣t✐♦♥ ❝❛♥ ❜❡ ♠♦❞❡❧❡❞ ❛s ♣r❡❞❛t✐♦♥ ♣r♦❝❡ss✳ ❍♦✇❡✈❡r

t❤✐s ❛❞❞s s♦♠❡ ❝♦♠♣❧❡①✐t② t♦ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ s♦♠❡ ❛❧❣❡❜r❛ t♦ t❤❡

♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧✳ ❲❡ ❝♦♥s✐❞❡r t❤❛t ❛t ❧❡❛st q✉❛❧✐t❛t✐✈❡❧② t❤❡ ❡✛❡❝t

♦❢ t❤❡ s✉❜str❛t❡ ✐s ✐♠♣❧✐❝✐t❧② ✐♥❝❧✉❞❡❞ ✐♥ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ t❤r♦✉❣❤ t❤❡ ✉s❡ ♦❢

❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❣r♦✇t❤ ❢✉♥❝t✐♦♥✳

✸✳✶✳✼ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼

◆♦✇ ✇❡ ♣r♦♣♦s❡ t♦ ❞❡r✐✈❡ ❛ ❞❡t❡r♠✐♥✐st✐❝ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ ❛♣♣r♦①✐♠❛t✐♥❣

t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✉s✐♥❣ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ t❡❝❤♥✐q✉❡s✳ ❚❤❡

♣r✐♥❝✐♣❧❡ ♦❢ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ t❡❝❤♥✐q✉❡ ✐s t♦ ❞❡r✐✈❡ t❤❡ ❡q✉❛t✐♦♥s t❤❛t

❞❡s❝r✐❜❡ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥ts✳ ❚❤❡ ✜rst ♠♦♠❡♥t

✐s t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ❛♥❞ ❝♦♥t❛✐♥s ♥♦ s♣❛t✐❛❧ ✐♥❢♦r♠❛t✐♦♥ ❛❜♦✉t t❤❡ ♣❛tt❡r♥✳ ❚❤❡

s❡❝♦♥❞ ♠♦♠❡♥t ♠❡❛s✉r❡ t❤❡ ✈❛r✐❛t✐♦♥ ♦❢ t❤❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐♥ s♣❛❝❡ ❛♥❞ ✐s

r❡♣r❡s❡♥t❡❞ ❜② t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs ♦❢ ✐♥❞✐✈✐❞✉❛❧s s❡♣❛r❛t❡❞ ✇✐t❤ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡

ξ✳ ❲❡ ✜rst st❛rt ❜② ❞❡✜♥✐♥❣ t❤❡s❡ ♠♦♠❡♥ts ❢♦r ❛ s❡t ♦❢ n ✐♥❞✐✈✐❞✉❛❧s t❤❛t ✐♥❤❛❜✐t

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✸✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✸✺

✭❛✮

✭❜✮

❋✐❣✉r❡ ✸✳✶✿ ❈♦♠♣❛r✐s♦♥ ♦❢ ❝♦❧♦♥② ♣❛tt❡r♥ s✐♠✉❧❛t❡❞ ✇✐t❤ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ ✭❛✮✮ ❛♥❞

t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✭❜✮ ✐♥ t❤❡ ❝❛s❡ ♦❢ ✬r❡❛❝t✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡

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✸✻

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

✭❛✮

✭❜✮

❋✐❣✉r❡ ✸✳✷✿ ❈♦♠♣❛r✐s♦♥ ♦❢ ❝♦❧♦♥② ♣❛tt❡r♥ s✐♠✉❧❛t❡❞ ✇✐t❤ t❤❡ ❞❡t❛✐❧❡❞ ■❇▼ ✭❝✮✮ ❛♥❞

t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✭❞✮ ✐♥ t❤❡ ❝❛s❡ ♦❢ ✬❞✐✛✉s✐♦♥✲❧✐♠✐t❡❞✬ r❡❣✐♠❡

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✸✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✸✼

❛ ❝♦♥t✐♥✉♦✉s s♣❛❝❡ ❛♥❞ ♦❝❝✉♣②✐♥❣ ❝♦♥t✐♥✉♦✉s ♣♦s✐t✐♦♥s xi✱ i = 1..n t❤❡♥ ✇❡ ❞❡r✐✈❡

t❤❡✐r ❞②♥❛♠✐❝❛❧ ❡q✉❛t✐♦♥s✳

❚❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ ♠♦♠❡♥ts ❝❛♥ ❜❡ ❝❛❧❝✉❧❛t❡❞ ♦♥ t❤❡ ♣❛tt❡r♥ ②✐❡❧❞❡❞ ❜② t❤❡

■❇▼ ❛♥❞ ❝♦♠♣❛r❡❞ t♦ t❤♦s❡ ♦❜t❛✐♥❡❞ ❜② s♦❧✈✐♥❣ ♥✉♠❡r✐❝❛❧❧② t❤❡ ♠♦♠❡♥t ♠♦❞❡❧

❡q✉❛t✐♦♥s✳ ❚❤❡ ❝❛❧❝✉❧❛t✐♦♥ ♦❢ t❤❡ ✜rst ♠♦♠❡♥t ❢r♦♠ t❤❡ ■❇▼ s✐♠✉❧❛t✐♦♥ r❡s✉❧ts

✐s ♣❡r❢♦r♠❡❞ s✐♠♣❧② ❜② ❝♦✉♥t✐♥❣ t❤❡ ♥✉♠❜❡r ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ ❞✐✈✐❞✐♥❣ ❜② t❤❡

❞♦♠❛✐♥ ❛r❡❛ t♦ ❣❡t ❛♥ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦✈❡r t❤❡ ❞♦♠❛✐♥✳ ❚❤❡ s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥t

✐s ♠❡❛s✉r❡❞ t❤r♦✉❣❤ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✳ ❚❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥

C(ξ) ❣✐✈❡s t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❧♦❝❛t❡❞ ❛t ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ ❢r♦♠

❛ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧✳ ❲❡ ❝❛❧❝✉❧❛t❡ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❞❡♥s✐t② ❢✉♥❝t✐♦♥ ❢♦r ❛ ❣✐✈❡♥

♣❛tt❡r♥ p ❢♦r♠❡❞ ✇✐t❤ n ✐♥❞✐✈✐❞✉❛❧s ❛s ✐♥ ❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪ ❜② ❝♦✉♥t✐♥❣ ❢♦r ❛ ❢♦❝❛❧

✐♥❞✐✈✐❞✉❛❧ ❛t ❧♦❝❛t✐♦♥ x = (x1, x2)✱ t❤❡ ♥✉♠❜❡r ♦❢ ♣❛✐r❡❞ ✐♥❞✐✈✐❞✉❛❧s ✇✐t❤✐♥ t❤❡

sq✉❛r❡ (x1 + ξ1, x1 + ξ1 + dξ1) × (x2 + ξ2, x2 + ξ2 + dξ2)✱ ✉s✐♥❣ ❛ s✉✣❝✐❡♥t❧② s♠❛❧❧

s♣❛t✐❛❧ r❡s♦❧✉t✐♦♥ dξ = (dξ1, dξ2)✳ ❲❡ r❡♣❡❛t t❤✐s ♣r♦❝❡❞✉r❡ ❢♦r ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧ ✐♥

t✉r♥ ❜❡✐♥❣ t❤❡ ❢♦❝❛❧ ♦♥❡ ❛♥❞ ❞✐✈✐❞✐♥❣ t❤❡ t♦t❛❧ ❝♦✉♥t ❜② t❤❡ ❞♦♠❛✐♥ ❛r❡❛ L2 ❛♥❞

❜② dξ1dξ2 ②✐❡❧❞s t❤❡ ♣❛✐r ❞❡♥s✐t② ❛t ❞✐st❛♥❝❡ ξ✳ ❚❤❡ r❡s✉❧t ✐s ❛ ♠❛tr✐①✳ ❚❤❡ ❝❡♥tr❛❧

✈❛❧✉❡ ♦❢ t❤❡ ♠❛tr✐① ❝♦rr❡s♣♦♥❞s t♦ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❡①♣❡r✐❡♥❝❡❞ ❜②

❛ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧ ❛t ❞✐st❛♥❝❡s s♠❛❧❧❡r t❤❛♥ t❤❡ s♣❛t✐❛❧ r❡s♦❧✉t✐♦♥ dξ✳ ❚❤❡ ♠❛tr✐① ❝❛♥

❜❡ ✉♥❞❡rst♦♦❞ ❜② ✐♠❛❣✐♥✐♥❣ t❤❛t ❛ ✈✐rt✉❛❧ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧ ✐s ❧♦❝❛t❡❞ ✐♥ t❤❡ ❝❡♥t❡r✳

❚❤❡ ♠❛tr✐① t❤❛♥ ❝♦rr❡s♣♦♥❞ t♦ t❤❡ ❛✈❡r❛❣❡ ❵✐♥❞✐✈✐❞✉❛❧s✬❡②❡ ✈✐❡✇✬ ♦❢ ✐ts ❡♥✈✐r♦♥♠❡♥t✳

❋✐❣✉r❡ ✸✳✸ s❤♦✇s t✇♦ s♥❛♣s❤♦ts ♦❢ ❛♥ ■❇▼ s✐♠✉❧❛t✐♦♥ ♦❢ t✇♦ ❝♦❧♦♥✐❡s✳ ❚❤❡ ❝♦❧♦♥✐❡s

s❤♦✇ ❞✐✛❡r❡♥t s❤❛♣❡s✳ ❚❤❡ ❜❛❝t❡r✐❛ ✐♥ t❤❡ ✜rst s❡❡♠s ❞✐str✐❜✉t❡❞ ✉♥✐❢♦r♠❧② ✇❤❡r❡

❛s t❤❡② ❛r❡ ♦r❣❛♥✐③❡❞ ✐♥ s♠❛❧❧ ❣r♦✉♣s ✐♥ t❤❡ s❡❝♦♥❞ ♣❛tt❡r♥✳ ❋✐❣✉r❡ ✸✳✹ r❡♣♦rts t❤❡

❝♦rr❡s♣♦♥❞✐♥❣ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s ✭C(ξ) ♠❛tr✐❝❡s ♣❧♦tt❡❞ ✉s✐♥❣ ▼❛t❧❛❜✮✳ ❚❤❡

♠❛tr✐❝❡s s❤♦✉❧❞ ♥♦t ❜❡ ❝♦♥❢✉s❡❞ ✇✐t❤ t❤❡ ❝♦❧♦♥② ♣❛tt❡r♥ ✐ts❡❧❢✳ ❚❤❡ ♠❛tr✐❝❡s ❞❡✲

s❝r✐❜❡s t❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ❡①♣❡r✐❡♥❝❡ ❜② ❛♥ ✐♥❞✐✈✐❞✉❛❧ ✇✐t❤✐♥ t❤❡ ❝♦❧♦♥②

❛t ❞✐✛❡r❡♥t ❞✐st❛♥❝❡s✳ ❆ ♣❡❛❦ ✐♥ t❤❡ ❝❡♥t❡r ♦❢ t❤❡ ♠❛tr✐① ✐♥❞✐❝❛t❡s t❤❛t t❤❡ ✐♥❞✐✲

✈✐❞✉❛❧s ❡①♣❡r✐❡♥❝❡ ❛ ❤✐❣❤ ❞❡♥s✐t② ♦❢ ♥❡✐❣❤❜♦rs ❛t s❤♦rt ❞✐st❛♥❝❡s✳ ❚❤❡s❡ ❞❡♥s✐t✐❡s

t❡♥❞ t♦ ✈❛♥✐s❤ ❛t ❤✐❣❤❡r ❞✐st❛♥❝❡s✳ ❚❤❡ ♠❛tr✐❝❡s ❛r❡ ♥♦r♠❛❧✐③❡❞ s✉❝❤ t❤❛t ❛ ✈❛❧✉❡

♦❢ ✶ ❝♦rr❡s♣♦♥❞s t♦ ❛ P♦✐ss♦♥✲❧✐❦❡ ♣❛tt❡r♥s ✇❤❡r❡ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛r❡ ✉♥✐❢♦r♠❧② ❞✐s✲

tr✐❜✉t❡❞ ♦✈❡r t❤❡ ❞♦♠❛✐♥✳ ❱❛❧✉❡s ❤✐❣❤❡r t❤❛♥ ♦♥❡ ✐♥❞✐❝❛t❡s ❛♥ ❛❣❣r❡❣❛t❡❞ ♣❛tt❡r♥

♠❡❛♥✐♥❣ t❤❛t t❤❡ ❞❡♥s✐t② ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐s ❤✐❣❤❡r t❤❛♥ ✇❤❛t ✇♦✉❧❞

❜❡ ❡①♣❡❝t❡❞ ✐❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✇❡r❡ ❞✐str✐❜✉t❡❞ ✉♥✐❢♦r♠❧②✳ ❚❤❡ ❝♦♠♣❛r✐s♦♥ ♦❢ t❤❡

♣❛✐r ❝♦rr❡❧❛t✐♦♥ ♠❛tr✐❝❡s ❝♦♥✜r♠ t❤❛t t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✇✐t❤✐♥ t❤❡ ❝♦❧♦♥✐❡s ✐♥ ✜❣✉r❡

✸✳✸ ❡①♣❡r✐❡♥❝❡ ❞✐✛❡r❡♥t ❧♦❝❛❧ ❝♦♥❞✐t✐♦♥s ✐♥ t❡r♠ ♦❢ ♥❡✐❣❤❜♦r ❞❡♥s✐t✐❡s✳ ❚❤❡ ♣r♦✜❧❡s

♦❢ t❤❡ ❈❛rt❡s✐❛♥ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ♣❧♦tt❡❞ ✐♥ ✜❣✉r❡ ✸✳✹ t❤❛t t❤❡ ♣❛✐r ❝♦r✲

r❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ t❛❦❡s ✈❛❧✉❡s ❝❧♦s❡ t♦ ✶ ❢♦r t❤❡ ✜rst ❝♦❧♦♥② ✐♥❞✐❝❛t✐♥❣ t❤❡ ❛❜s❡♥❝❡

♦❢ ❛♥② s♣❛t✐❛❧ str✉❝t✉r❡✱ ✇❤❡r❡❛s t❤❡ s❡❝♦♥❞ ❢✉♥❝t✐♦♥ ♣❡❛❦❡❞ ❛t s❤♦rt ❞✐st❛♥❝❡ ❛♥❞

✈❛♥✐s❤❡❞ t♦ ♦♥❡ ❛t ❧❛r❣❡ ❞✐st❛♥❝❡s✳ ❚❤❡ ♣❡❛❦ ❛t s❤♦rt ❞✐st❛♥❝❡s ✐♥❞✐❝❛t❡s t❤❛t t❤❡

✐♥❞✐✈✐❞✉❛❧s ❛r❡ ❧✐❦❡❧② t♦ ❡①♣❡r✐❡♥❝❡ ❤✐❣❤❡r ❞❡♥s✐t✐❡s ♦❢ ♥❡✐❣❤❜♦rs t❤❛♥ ✇❤❛t ✇♦✉❧❞

❜❡ ❡①♣❡r✐❡♥❝❡❞ ✐♥ t❤❡ ❛❜s❡♥❝❡ ♦❢ ❛♥② s♣❛t✐❛❧ str✉❝t✉r❡✳ ❚❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥

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✸✽

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

❝❛♣t✉r❡s ✇❡❧❧ t❤❡ ❤❡t❡r♦❣❡♥❡✐t✐❡s ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳

✸✳✶✳✼✳✶ ❉❡r✐✈✐♥❣ t❤❡ ❞②♥❛♠✐❝ ❡q✉❛t✐♦♥s ♦❢ t❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ ♠♦♠❡♥t

❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✜rst ♠♦♠❡♥t ✭♠❡❛♥ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✮ ✐s ❣✐✈❡♥ ❜② t❤❡

❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥✿

dN

dt= (b1 − d1)N − b′1

C(ξ)K

(

||ξ||

wd

)

dξ ✭✸✳✸✮

❚❤❡ ✜rst t❡r♠ ♦♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ✐s ♥❡✐❣❤❜♦r❤♦♦❞✲✐♥❞❡♣❡♥❞❡♥t ❝♦♠♣♦♥❡♥ts

♦❢ ❞✐✈✐s✐♦♥s ❛♥❞ ❞❡❛t❤✱ ❛♥❞ t❤❡ s❡❝♦♥❞ t❡r♠ ✐s t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞✲❞❡♣❡♥❞❡♥t ❝♦♠♣♦✲

♥❡♥ts ♦❢ ❞✐✈✐s✐♦♥s✳ ❚❤❡ ✐♥t❡❣r❛❧ t❡r♠ ✐♥✈♦❧✈❡ t❤❡ ♣❛✐r ❞❡♥s✐t② ❢✉♥❝t✐♦♥ C(ξ) ❛♥❞ t❤❡

✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ||/wd)✳ ❚❤✐s t❡r♠ ❡♥❝♦♠♣❛ss t❤❡ ❡✛❡❝t ♦❢ t❤❡ ❧♦❝❛❧ ❡♥✈✐r♦♥✲

♠❡♥t ♦♥ t❤❡ ♠❡❛♥ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✇❤✐❝❤ ✐s t❤❡ r❡s✉❧t ♦❢ t❤❡ s♣❛t✐❛❧ str✉❝t✉r❡✱

❛s ❣✐✈❡♥ ❜② C(ξ)✱ ❛♥❞ ♦♥ t❤❡ ❡①t❡♥t t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❡①♣❡r✐❡♥❝❡ t❤❡ ❡✛❡❝t ♦❢ t❤✐s

str✉❝t✉r❡ ❛s ❣✐✈❡♥ ❜② K(||ξ||/wd)✳ ◆♦t❡ t❤❛t ✐❢ t❤❡ s✐❞❡ ♦❢ t❤❡ ✉♥✐❢♦r♠ ✐♥t❡r❛❝t✐♦♥

❦❡r♥❡❧✱ wd✱ ✐s ❡q✉❛❧ t♦ t❤❡ s✐❞❡ L ♦❢ t❤❡ ❞♦♠❛✐♥ t❤❛♥ ❡q✉❛t✐♦♥ ✸✳✸ ❝❛♥ ❜❡ s✐♠♣❧✐✜❡❞

t♦ ❛ s✐♠♣❧❡ ♥♦♥ s♣❛t✐❛❧ ▲♦t❦❛✲✈♦❧t❡r❛ ❡q✉❛t✐♦♥ ❬▲❛✇ ✷✵✵✵❪✿

dN

dt= (b1 − d1)N − b′1N

2 ✭✸✳✹✮

■♥ t❤✐s ❝❛s❡ t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ ❛♥② ✐♥❞✐✈✐❞✉❛❧ ✐s ❡q✉❛❧❧② ❛✛❡❝t❡❞ ❜② ❛❧❧ t❤❡

♦t❤❡r ✐♥❞✐✈✐❞✉❛❧s✳ ❍♦✇❡✈❡r ✐♥ ♠♦st ♠✐❝r♦❜✐❛❧ s②st❡♠ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ♣❡r❝❡✐✈❡ ♦♥❧②

t❤❡✐r ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t✳ ❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ s❡❝♦♥❞ ♠♦♠❡♥t ❛❝❝♦✉♥ts ❢♦r t❤❡ ♣r♦✲

❝❡ss❡s ✭❞✐✈✐s✐♦♥ ❛♥❞ ❞❡❛t❤✮ t❤❛t ❛✛❡❝t t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ✈❡❝t♦r✐❛❧

❞✐st❛♥❝❡ ξ✳

dC(ξ)

dt=

(

dC(ξ)

dt

)

division

+

(

dC(ξ)

dt

)

death

✭✸✳✺✮

❚❤❡ t❡r♠s ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ❞❡♥♦t❡ r❡s♣❡❝t✐✈❡❧② t❤❡ ❡✛❡❝t ♦❢ ❞✐✈✐s✐♦♥ ❛♥❞

❞❡❛t❤ ❡✈❡♥ts ♦♥ t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs C(ξ)✳ ❚❤❡ ❡✛❡❝t ♦❢ t❤❡ ❞❡❛t❤ ✐s str❛✐❣❤t❢♦r✇❛r❞✳

❈♦♥s✐❞❡r ❛ ♣❛✐r ♦❢ ✐♥❞✐✈✐❞✉❛❧s s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ✳ ■❢ ♦♥❡ ♦❢ t❤❡s❡ t✇♦

✐♥❞✐✈✐❞✉❛❧ ❞✐❡s t❤❛♥ ✇❡ ❧♦♦s❡ ❛ ♣❛✐r ♦❢ ✐♥❞✐✈✐❞✉❛❧s s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ✳ ❚❤❡

r❛t❡ ❛t ✇❤✐❝❤ ✇❡ ❧♦♦s❡ ♣❛✐rs ♦❢ ✐♥❞✐✈✐❞✉❛❧ s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ ✐s ❣✐✈❡♥ ❜②✿

(

dC(ξ)

dt

)

death

= −2d1C(ξ) ✭✸✳✻✮

❚❤❡ ❡✛❡❝t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❞✐✈✐s✐♦♥ ❡✈❡♥ts ♦♥ t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs ❛t ❞✐st❛♥❝❡ ξ

✐s ♠♦r❡ ❝♦♠♣❧✐❝❛t❡❞ ❛♥❞ ✐s ❣✐✈❡♥ ❜② t❤❡ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥✿

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✸✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✸✾

✭❛✮

✭❜✮

❋✐❣✉r❡ ✸✳✸✿ ❊①❛♠♣❧❡s ♦❢ ❝♦❧♦♥② ♣❛tt❡r♥s ❜♦t❤ ✐♥✐t✐❛❧✐③❡❞ ✇✐t❤ ❛ s✐♥❣❧❡ ❝❡❧❧ ✐♥ t❤❡

❝❡♥t❡r ♦❢ t❤❡ ❞♦♠❛✐♥✳

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✹✵

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

✭❛✮

✭❜✮

❋✐❣✉r❡ ✸✳✹✿ ❈❛rt❡s✐❛♥ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s ✭♠❛tr✐❝❡s C(ξ)✮ ❝♦rr❡s♣♦♥❞✐♥❣ t♦

t❤❡ ♣❛tt❡r♥s ✐♥ ✜❣✉r❡ ✸✳✸✳ ❚❤❡ ❜❧❛❝❦ ❧✐♥❡s ✐♥❞✐❝❛t❡s t❤❡ r❛❞✐❛❧ ♣r♦✜❧❡s t❤❛t ❛r❡

♣❧♦tt❡❞ ✐♥ t❤❡ ♥❡①t ✜❣✉r❡ ✭✜❣✉r❡ ✸✳✺✮

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✸✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✹✶

✭❛✮

✭❜✮

❋✐❣✉r❡ ✸✳✺✿ ❘❛❞✐❛❧ ♣r♦✜❧❡s ♦❢ t❤❡ ❈❛rt❡s✐❛♥ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✭❜❧❛❝❦ ❧✐♥❡s ✐♥

✜❣✉r❡ ✸✳✹✮

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✹✷

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

(

dC(ξ)

dt

)

division

=

+2b1NK

(

||ξ||

wb

)

−2b′1K

(

||ξ||

wb

)∫

K

(

||ξ′′||

wd

)

C(ξ′′)dξ′′

+2b1

C(ξ + ξ′)K

(

||ξ′||

wb

)

dξ′

−2b′1

∫ ∫

K

(

||ξ′||

wb

)

K

(

(||ξ′′||

wd

)

T (ξ + ξ′, ξ′′)dξ′dξ′′

−2b′1

C(ξ + ξ′)K

(

(||ξ + ξ′||

wd

)

K

(

(||ξ′||

wb

)

dξ′ ✭✸✳✼✮

❚❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ✐s ❢♦r♠❡❞ ✇✐t❤ ✜✈❡ t❡r♠s t❤❛t ❞❡s❝r✐❜❡ t❤❡ ✈❛r✐❛t✐♦♥ ✐♥ t❤❡

❞❡♥s✐t② ♦❢ (i, j) ♣❛✐rs ❛t ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ r❡s✉❧t✐♥❣ ❢r♦♠ ❞✐✈✐s✐♦♥ ❡✈❡♥ts✳ ❚♦ ✉♥✲

❞❡rst❛♥❞ t❤❡ ♣r❡❝✐s❡ ✐♥t❡r♣r❡t❛t✐♦♥ ♦❢ ❡❛❝❤ t❡r♠ ✇❡ ♣r♦❝❡❡❞ ❛s ✐♥ ❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪

❜② ❢♦❝✉s✐♥❣ ♦♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ♦❢ t❤❡ (i, j) ♣❛✐r✳

• t❤❡ ✜rst t❡r♠ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧ i

♣r♦❞✉❝✐♥❣ ❛ ♥❡✇ ✐♥❞✐✈✐❞✉❛❧ j ❧♦❝❛t❡❞ ❛t ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ✳ ▼✉❧t✐♣❧②✐♥❣ t❤❡

♠❡❛♥ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s N ❛♥❞ ❜② t❤❡ ✐♥❞❡♣❡♥❞❡♥t ♣❡r ❝❛♣✐t❛ ❞✐✈✐s✐♦♥ r❛t❡

b1 ❣✐✈❡s t❤❡ r❛t❡ ♦❢ ♦❢ ❞✐✈✐s✐♦♥ ❡✈❡♥ts✳ ❚❤❡♥ ✇❡ ♠✉❧t✐♣❧② ❜② t❤❡ ♣r♦❜❛❜✐❧✐t②

t❤❛t t❤❡ ♥❡✇❧② ❢♦r♠❡❞ ❝❡❧❧ ✐s ❧♦❝❛t❡❞ ❛t ❞✐st❛♥❝❡ ξ ❢r♦♠ t❤❡ ♣❛r❡♥t ♣♦s✐t✐♦♥✳

❚❤❡ ❢❛❝t♦r ✷ ❛❝❝♦✉♥ts ❢♦r ♥❡✇❧② ❢♦r♠❡❞ ✐♥❞✐✈✐❞✉❛❧s t❤❛t ❞✐s♣❡rs❡ t♦ ❞✐st❛♥❝❡

−ξ ✇❤✐❝❤ ❛❧s♦ ❢♦r♠ ❛ ♥❡✇ ♣❛✐r (j, i) ❛t ❞✐st❛♥❝❡ ξ

• t❤❡ s❡❝♦♥❞ t❡r♠ ❝♦rr❡❝ts t❤❡ ✐♥❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ r❛t❡ ❝❛❧❝✉❧❛t❡❞ ❜② t❤❡ ✜rst

t❡r♠ ❜② t❛❦✐♥❣ ✐♥t♦ ❛❝❝♦✉♥t t❤❡ ♥❡❣❛t✐✈❡ ❡✛❡❝t ♦❢ t❤❡ ♣♦ss✐❜❧❡ ♣r❡s❡♥❝❡ ♦❢

♥❡✐❣❤❜♦rs ❛r♦✉♥❞ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i✳ ❚❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♥❡✐❣❤❜♦rs

❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ✐s ❣✐✈❡♥ ❜② t❤❡ ✐♥t❡❣r❛❧∫

K(||ξ′′||/wd)C(ξ′′)dξ′′✳

▼✉❧t✐♣❧②✐♥❣ ❜② t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ r❛t❡ b′1 ❛♥❞ ❜② 2K(||ξ||/wb)

❣✐✈❡s t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❝♦rr❡❝t✐♦♥ ♦❢ t❤❡ ✜rst t❡r♠✳

• t❤❡ t❤✐r❞ t❡r♠ ❛❧s♦ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥✱ ❜✉t ❢♦❝✉s❡s

♦♥ t❤❡ ♥❡✇ ♣❛✐r t❤❛t t❤❡ ♦✛s♣r✐♥❣ ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧ i ❢♦r♠s ✇✐t❤ ❛♥❞ ✐♥❞✐✈✐❞✉❛❧ j

❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ+ ξ′ ❢r♦♠ i✳ ❚❤❡ ♣❡r ❝❛♣✐t❛ r❛t❡ ♦❢ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t

r❛t❡ ♦❢ ❞✐✈✐s✐♦♥ ✐s b1✱ t❤❡ ❞❡♥s✐t② ♦❢ (i, j) ♣❛✐rs ✐s C(ξ + ξ′) ❛♥❞ t❤❡ s♣❛t✐❛❧

❞❡♥s✐t② ♦❢ ♦✛s♣r✐♥❣ s❡tt❧✐♥❣ ❛r♦✉♥❞ t❤❡ i ♣❛r❡♥t ✐s K(||ξ′||/wb)✳ ▼✉❧t✐♣❧②✐♥❣

t❤❡s❡ t❤r❡❡ ❢❛❝t♦rs ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ♣♦ss✐❜❧❡ ❞✐st❛♥❝❡s ξ′ ♦❢ ♦✛s♣r✐♥❣

❞✐s♣❡rs❛❧ ②✐❡❧❞s t❤❡ t❤✐r❞ t❡r♠✳

• t❤❡ ❢♦✉rt❤ t❡r♠ ✐s ❛ ❝♦rr❡❝t✐♦♥ ♦❢ t❤❡ ❞❡♥s✐t② ✐♥❞❡♣❡♥❞❡♥t t❤✐r❞ t❡r♠ t♦ ❛❝❝♦✉♥t

❢♦r t❤❡ ❡✛❡❝t ♦❢ ♥❡✐❣❤❜♦rs ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i t❤❛t r❡❞✉❝❡s ✐ts r❛t❡ ♦❢ ♣r♦❞✉❝✐♥❣

♥❡✇ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ✐♥ t❤❡ ♣❛✐r (i, j) ❛t

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✸✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✹✸

❞✐st❛♥❝❡ ξ + ξ′ ❝❛♥ ❜❡ ♠♦❞✐✜❡❞ ❜② t❤❡ ♣r❡s❡♥❝❡ ♦❢ ❛ ♥❡✐❣❤❜♦r k ❧♦❝❛t❡❞ ❛t

❞✐st❛♥❝❡ ξ′′ ❢r♦♠ i✳ ❚❤❡ ❞❡♥s✐t② ♦❢ tr✐♣❧❡t ♦❢ ✐♥❞✐✈✐❞✉❛❧s (i, j, k) ✐s T (ξ+ξ′, ξ′′)✱

t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ ❢♦r t❤❡ (i, k) ♣❛✐r ②✐❡❧❞s K(||ξ′′||/wd) ❛♥❞ t❤❡ s♣❛t✐❛❧

❞❡♥s✐t② ♦❢ ♦✛s♣r✐♥❣ ❛r♦✉♥❞ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ✐s K(||ξ′||/wb)✳ ▼✉❧t✐♣❧②✐♥❣ t❤❡s❡

❢❛❝t♦rs ✇✐t❤ t❤❡ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ❜✐rt❤ r❛t❡ ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ♣♦ss✐❜❧❡

❞✐st❛♥❝❡s ξ′ ❛♥❞ ✐♥t❡r❛❝t✐♦♥ ❞✐st❛♥❝❡s ξ′′ ❣✐✈❡s t❤❡ ❢♦rt❤ t❡r♠✳

• t❤❡ ✜❢t❤ t❡r♠ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❡✛❡❝t ♦❢ tr✐♣❧❡t (i, j, k) ❜✉t ❞♦ ♥♦t ✐♥❝❧✉❞❡

t❤❡ ❡✛❡❝t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ j ♦♥ t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i✳ ❚❤✉s

t❤❡ ✜❢t❤ t❡r♠ ❛❞❞s t❤✐s ❝♦rr❡❝t✐♦♥ ❜② ♠✉❧t✐♣❧②✐♥❣ t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs (i, j)

s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ + ξ′ ✇✐t❤ t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ + ξ′||/wd)✳

❚❤❡ ❝♦rr❡❝t✐♦♥ t❡r♠ ✐s ♦❜t❛✐♥❡❞ ❜② ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ♣♦ss✐❜❧❡ ❞✐st❛♥❝❡s ξ′ ❛♥❞

❜② ♠✉❧t✐♣❧②✐♥❣ ❜② t❤❡ ♣r♦❜❛❜✐❧✐t② ❞❡♥s✐t② K(||ξ′||/wb) ♦❢ ❤❛✈✐♥❣ ❛♥ ♦✛s♣r✐♥❣

❛t ❞✐st❛♥❝❡ ξ′ ❢r♦♠ i ❛♥❞ t❤❡ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ r❛t❡ b′1

■♥ t❤❡ t❤r❡❡ ❧❛st t❡r♠s ✇❡ ❢♦❝✉s❡❞ ♦♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i✳ ❆♥❛❧♦❣♦✉s ❡✈❡♥ts ❝❛♥

♦❝❝✉r t♦ t❤❡ ✐♥❞✐✈✐❞✉❛❧ j✳ ❲❡ t❛❦❡ t❤✐s ✐♥ ❝♦♥s✐❞❡r❛t✐♦♥ ❜② ♠✉❧t✐♣❧②✐♥❣ t❤❡s❡ t❡r♠s

❜② ❛ ❢❛❝t♦r ✷✳ ❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✜rst ♠♦♠❡♥t ✐♥✈♦❧✈❡ t❤❡ s❡❝♦♥❞ ♠♦♠❡♥t✱ t❤❛t ♦❢

t❤❡ s❡❝♦♥❞ ♠♦♠❡♥t ✐♥✈♦❧✈❡s t❤❡ ❞❡♥s✐t② ♦❢ tr✐♣❧❡t ❞❡♥♦t❡❞ T (ξ + ξ′, ξ′′)✳ ❲❡ ❝❛♥ ✐♥

♣r✐♥❝✐♣❧❡ ❝♦♥t✐♥✉❡ ✇✐t❤ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ t❤✐r❞ ♠♦♠❡♥t ✭tr✐♣❧❡t ❞❡♥s✐t✐❡s✮ ✇❤✐❝❤

s❤♦✉❧❞ ✐♥✈♦❧✈❡ t❤❡ ❤✐❣❤❡r ♦r❞❡r ♠♦♠❡♥ts✳ ❚♦ ❡s❝❛♣❡ t❤✐s ❝❛s❝❛❞❡ ♦❢ ❞❡♣❡♥❞❡♥❝✐❡s

❉✐❡❝❦♠❛♥♥ ❛♥❞ ▲❛✇ ❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪ ♣r♦♣♦s❡❞ t♦ tr✉♥❝❛t❡ t❤❡ ♠♦♠❡♥t ❤✐❡r❛r❝❤②

❜② ❡①♣r❡ss✐♥❣ t❤❡ t❤✐r❞ ♠♦♠❡♥t ✐♥ t❡r♠s ♦❢ t❤❡ s❡❝♦♥❞ ❛♥❞ ✜rst ♠♦♠❡♥t✳ ❙✉❝❤

❡①♣r❡ss✐♦♥ ❛r❡ ❝❛❧❧❡❞ ♠♦♠❡♥t ❝❧♦s✉r❡s ❛♥❞ s❤♦✉❧❞ s❛t✐s❢② ❛ ♥✉♠❜❡r ♦❢ ❝♦♥❞✐t✐♦♥s ❞❡✲

t❛✐❧❡❞ ✐♥ ❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪✳ ❚❤❡ ❝❤♦✐❝❡ ♦❢ t❤❡ ♠♦♠❡♥t ❝❧♦s✉r❡ ♠❛② ❤❛✈❡ ❛♥ ✐♠♣❛❝t

♦♥ t❤❡ q✉❛❧✐t② ♦❢ t❤❡ ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ✉♥❞❡r❧②✐♥❣ ✐♥❞✐✈✐❞✉❛❧ ♣r♦❝❡ss❡s✳ ❚❤✐s

✐s ♦❢t❡♥ ❛ss❡ss❡❞ ❜② ❝♦♠♣❛r✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ t♦ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✉♥❞❡r❧②✲

✐♥❣ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪✳ ❲❡ ✉s❡ t❤❡ ❢♦❧❧♦✇✐♥❣ ❛♣♣r♦①✐♠❛t✐♦♥

❝❧♦s✉r❡ ❡q✉❛t✐♦♥ ✇❤✐❝❤ ❡①♣r❡ss❡s t❤❡ t❤✐r❞ ♠♦♠❡♥t ❛s ❛ ❢✉♥❝t✐♦♥ ♦❢ t❤❡ s❡❝♦♥❞ ❛♥❞

✜rst ♠♦♠❡♥ts✿

T (ξ, ξ′) =C(ξ)C(ξ′)

N✭✸✳✽✮

✸✳✶✳✽ ❙♦❧✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧

❚❤❡ s②st❡♠ ❢♦r♠❡❞ ✇✐t❤ ❡q✉❛t✐♦♥s ✸✳✸✱ ✸✳✼ ❛♥❞ ✸✳✽ ❝❛♥ ❜❡ s♦❧✈❡❞ ❛ss✉♠✐♥❣ ♣❡r✐♦❞✐❝

❜♦✉♥❞❛r② ❝♦♥❞✐t✐♦♥s ❛♥❞ t❛❦✐♥❣ ❛s ✐♥✐t✐❛❧ ❝♦♥❞✐t✐♦♥s ❛♥ ✐♥✐t✐❛❧ ❞❡♥s✐t② N(t = 0)

♦❢ ✐♥❞✐✈✐❞✉❛❧s ❞✐str✐❜✉t❡❞ ✉♥✐❢♦r♠❧② ✇❤✐❝❤ ②✐❡❧❞s ❛♥ ✐♥✐t✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❞❡♥s✐t②

❢✉♥❝t✐♦♥ C(ξ, t = 0) = N2✳ ❚❤❡ s②st❡♠ ❝❛♥ ❜❡ s♦❧✈❡❞ ✐♥ t❤❡ ❈❛rt❡s✐❛♥ ❝♦♦r❞✐♥❛t❡s

♦r ✐♥ t❤❡ r❛❞✐❛❧ ❝♦♦r❞✐♥❛t❡s ✭❜❡❝❛✉s❡ ♦❢ t❤❡ ✐s♦tr♦♣② ♦❢ t❤❡ ❞♦♠❛✐♥ ❛♥❞ t❤❡ r❛❞✐❛❧

s②♠♠❡tr② ♦❢ ❛❧❧ t❤❡ ♣r♦❝❡ss❡s✮✳ ❋♦r t❤❡ r❛❞✐❛❧ ❢♦r♠✉❧❛t✐♦♥ ♦❢ t❤❡s❡ ❡q✉❛t✐♦♥s r❡❢❡r

t♦ t❤❡ ❆♥♥❡①❡ ❆ ♦❢ t❤✐s ❝❤❛♣t❡r✳ ❲❡ ♣r❡s❡♥t ❤❡r❡ t❤❡ ♣r♦❝❡❞✉r❡ ❢♦r s♦❧✈✐♥❣ t❤❡

♠♦♠❡♥t ❞②♥❛♠✐❝ ❡q✉❛t✐♦♥ ✐♥ t❤❡ ❈❛rt❡s✐❛♥ ❝♦♦r❞✐♥❛t❡s✳

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✹✹

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

❋✐❣✉r❡ ✸✳✻✿ ❉✐s❝r❡t✐③❛t✐♦♥ ♦❢ t❤❡ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ s❡♣❛r❛t✐♥❣ t✇♦ ✐♥❞✐✈✐❞✉❛❧s

❚❤❡ st❛t❡ ✈❛r✐❛❜❧❡s ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛r❡ t❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥ts

N(t) ❛♥❞ C(ξ, t)✳ ❚❤❡ ✜rst ♠♦♠❡♥t N(t) ✐s ❛ r❡❛❧ ✈❛❧✉❡ ✭❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✮✳ ❚❤❡

s❡❝♦♥❞ ♠♦♠❡♥t C(ξ, t) ✐s ❛ ❢✉♥❝t✐♦♥ t❤❛t ❣✐✈❡s t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs ♦❢ ✐♥❞✐✈✐❞✉❛❧s

s❡♣❛r❛t❡❞ ❜② ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ = (ξ1, ξ2)✳ ❚♦ s♦❧✈❡ t❤❡ ♠♦♠❡♥t ❞②♥❛♠✐❝ ♠♦❞❡❧

✇❡ st❛rt ❜② ❞✐s❝r❡t✐③✐♥❣ t❤❡ ❡q✉❛t✐♦♥ ✸✳✸ ❛♥❞ ✸✳✼ ✇✐t❤ r❡s♣❡❝t t♦ s♣❛❝❡ ❛♥❞ t✐♠❡✳

• ❙♣❛t✐❛❧ ❞✐s❝r❡t✐③❛t✐♦♥ ❲❡ ❞✐s❝r❡t✐③❡ t❤❡ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ = (ξ1, ξ2) ✐♥t♦

ξ(i, j) = (ξ1(i), ξ2(j)) ✇✐t❤ i, j = −(n − 1)/2✳✳(n − 1)/2 ✭s❡❡ ✜❣✉r❡ ✸✳✻✮✳ ❚❤❡

❢✉♥❝t✐♦♥ C(ξ, t) ✐s ❡✈❛❧✉❛t❡❞ ♦♥❧② ✐♥ t❤❡s❡ ❞✐s❝r❡t✐③❡❞ ♣♦✐♥ts ❛♥❞ t❛❦❡s t❤❡ ❢♦r♠

♦❢ ❛ n× n sq✉❛r❡ ♠❛tr✐① C(i, j, t) ✇✐t❤ i, j = −(n− 1)/2✳✳(n− 1)/2

❋♦r t❤❡ ❝❛❧❝✉❧❛t✐♦♥ ♦❢ t❤❡ ✐♥t❡❣r❛❧ t❡r♠s ✐♥ ❡q✉❛t✐♦♥s ✸✳✸ ❛♥❞ ✸✳✼ ✇❡ ♥❡❡❞ t♦

❞✐s❝r❡t✐③❡ t❤❡ ❦❡r♥❡❧s K(||ξ||/wb) ❛♥❞ K(||ξ||/wbd)✳ ❲❡ ✉s❡ t❤❡ s❛♠❡ s♣❛t✐❛❧

r❡s♦❧✉t✐♦♥ dξ✳ ◆♦t❡ t❤❛t t❤❡ s♣❛t✐❛❧ r❡s♦❧✉t✐♦♥ dξ ❞❡♣❡♥❞s ♦♥ t❤❡ s✐③❡ ♦❢ t❤❡

✐♥t❡r❛❝t✐♦♥ ❛♥❞ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧s✳ ❆s t❤❡s❡ ❦❡r♥❡❧s ❞❡✜♥❡ t❤❡ s♣❛t✐❛❧ ❞✐st❛♥❝❡

♦✈❡r ✇❤✐❝❤ ❧♦❝❛❧ ✐♥t❡r❛❝t✐♦♥s t❛❦❡ ♣❧❛❝❡✱ t❤❡ s♣❛t✐❛❧ r❡s♦❧✉t✐♦♥ dξ s❤♦✉❧❞ ❜❡

s♠❛❧❧ ❝♦♠♣❛r❡❞ t♦ t❤❡ s✐③❡ ♦❢ t❤❡s❡ ❦❡r♥❡❧s✳ ❆ t②♣✐❝❛❧ r❡s♦❧✉t✐♦♥ t♦ ❞✐s❝r❡t✐③❡

●❛✉ss✐❛♥ ❦❡r♥❡❧s ✐s dξ = ((min(wb, wd)/5,min(wb, wd)/5) ✇❤❡r❡ min(wb, wd)

✐s s♠❛❧❧❡st ✈❛❧✉❡ ❜❡t✇❡❡♥ wb ❛♥❞ wd✳ ■♥ t❤✐s ✇♦r❦ ✇❡ ❝♦♥s✐❞❡r❡❞ ✐❞❡♥t✐❝❛❧

✉♥✐❢♦r♠ ❦❡r♥❡❧s ✭s❡❡ ✜❣✉r❡ ✸✳✼✮✳

• ❚✐♠❡ ❞✐s❝r❡t✐③❛t✐♦♥ ❲❡ ❞✐s❝r❡t✐③❡ t✐♠❡ ❞❡r✐✈❛t✐✈❡s ✐♥ ❡q✉❛t✐♦♥ ✸✳✸ ❛♥❞ ✸✳✼

✉s✐♥❣ ❛♥ ❡①♣❧✐❝✐t ❊✉❧❡r s❝❤❡♠❡ ✇✐t❤ ❛ t✐♠❡ st❡♣ ∆t = 1

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✸✳✷✳ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✇✐t❤ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✹✺

❋✐❣✉r❡ ✸✳✼✿ ❉✐s❝r❡t✐③❛t✐♦♥ ♦❢ ✐♥t❡r❛❝t✐♦♥ ❛♥❞ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧s K(||ξ||/wb) ❛♥❞

K(||ξ||/wd)✳ ❇♦t❤ ❦❡r♥❡❧s ❛r❡ ✉♥✐❢♦r♠ ✇✐t❤ ❛ ✇✐♥❞♦✇ ✇✐❞t❤ wb = wd = h = 5dξ

❚❤❡ ❞✐s❝r❡t✐③❡❞ s②st❡♠ ✐s ❢♦r♠❡❞ ✇✐t❤ n2 + 1 ❛❧❣❡❜r❛✐❝ ❡q✉❛t✐♦♥s ✇❤❡r❡ t❤❡ ✉♥✲

❦♥♦✇♥s ❛r❡ t❤❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s N ❛♥❞ t❤❡ n2 ❡❧❡♠❡♥ts ♦❢ t❤❡ ♠❛tr✐① C(ξ)✳

✸✳✷ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✇✐t❤ t❤❡ s✐♠♣❧✐✲

✜❡❞ ■❇▼

❲❡ ❝♦♠♣❛r❡ t❤❡ s✐♠✉❧❛t✐♦♥ r❡s✉❧ts t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ♦r t❤❡

❝❛s❡ ♦❢ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❣r♦✇t❤ ✭b′1 = 0✮ ❛♥❞ ❞❡♥s✐t②✲❞❡♣❡♥❞❛♥t ❣r♦✇t❤ ✭b′1 > 0✮✳

✸✳✷✳✶ ❉❡♥s✐t② ✐♥❞❡♣❡♥❞❡♥t ❣r♦✇t❤ ♠♦❞❡❧ ✭b′1 = 0✮

❚❤❡ ❝❛s❡ ♦❢ ❞❡♥s✐t② ✐♥❞❡♣❡♥❞❡♥t ❣r♦✇t❤ ✐♠♣❧✐❡s t❤❛t t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❤❛s ♥♦

✐♠♣❛❝t ♦♥ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤✐s ❝❛♥ ❜❡ s❡❡♥ ❢r♦♠ ❡q✉❛t✐♦♥ ✸✳✸✳

❇② s❡tt✐♥❣ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❣r♦✇t❤ ♣❛r❛♠❡t❡r t♦ ③❡r♦ b′1 = 0 t❤❡ ❡q✉❛t✐♦♥

s✐♠♣❧✐✜❡s t♦ ❛ ❝❧❛ss✐❝❛❧ ♥♦♥ s♣❛t✐❛❧ ♠❡❛♥ ✜❡❧❞ ❡q✉❛t✐♦♥✿

dN

dt= b1N − d1N ✭✸✳✾✮

❆s ✇❡ ❛ss✉♠❡❞ t❤❛t b1 = d1✱ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐s ❝♦♥st❛♥t ✭✐❢

N0 ✐s t❤❡ ✐♥✐t✐❛❧ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✱ t❤❛♥ N(t) = N0✮✳ ❋✐❣✉r❡ ✸✳✶✵ ❝♦♠♣❛r❡s t❤❡

❛✈❡r❛❣❡ ❞❡♥s✐t✐❡s ♦❢ ✐♥❞✐✈✐❞✉❛❧s ②✐❡❧❞❡❞ ❜② ❜♦t❤ ♠♦❞❡❧s ❢♦r t❤❡ ❝❛s❡ b′1 = 0 ❛♥❞ s❤♦✇s

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✹✻

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

✭❛✮ ❚✐♠❡❂✵ ✭❜✮ ❚✐♠❡❂✺✵

✭❝✮ ❚✐♠❡❂✶✵✵

❋✐❣✉r❡ ✸✳✽✿ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ s✐♠✉❧❛t✐♦♥ ♦❢ ♣❛tt❡r♥ ❢♦r♠❛t✐♦♥ ❢♦r b1 = d1 = 0.1✱

b′1 = 0.0

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✸✳✷✳ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✇✐t❤ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✹✼

❋✐❣✉r❡ ✸✳✾✿ ❘❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❢♦r b1 = d1 = 0.1✱

b′1 = 0.0

t❤❛t t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s r❡♠❛✐♥s ❝♦♥st❛♥t ✐♥ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞

t❤❛t ✐t ✢✉❝t✉❛t❡s ❛r♦✉♥❞ t❤❡ ✐♥✐t✐❛❧ ✈❛❧✉❡ ✐♥ t❤❡ ■❇▼✳

❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ ■❇▼ ❡♥❝♦♠♣❛ss ❛❞❞✐t✐♦♥❛❧ ✐♥❢♦r♠❛t✐♦♥s ❛❜♦✉t t❤❡ s♣❛t✐❛❧

♣❛tt❡r♥✳ ❆s ✇❡ ♠❡♥t✐♦♥❡❞ ❜❡❢♦r❡✱ t❤❡ ❛ss✉♠♣t✐♦♥ t❤❛t ❞❛✉❣❤t❡r ❝❡❧❧s ❛r❡ ❧♦❝❛t❡❞

✐♥ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡ ♠♦t❤❡r ❝❡❧❧s ✐s s✉✣❝✐❡♥t t♦ ♣r♦❞✉❝❡ s♣❛t✐❛❧ ♣❛tt❡r♥s✳

❋✐❣✉r❡ ✸✳✽ s❤♦✇s ❛♥ ✐❧❧✉str❛t✐♦♥ ♦❢ s✉❝❤ ♣❛tt❡r♥s✳ ❚❤❡ ✐♥✐t✐❛❧ ✉♥✐❢♦r♠ ❞✐str✐❜✉t✐♦♥ ♦❢

✐♥❞✐✈✐❞✉❛❧s ✐♥ ✜❣✉r❡ ✸✳✽✭❛✮ ❡✈♦❧✈❡s t♦✇❛r❞s ❛♥❞ ❛❣❣r❡❣❛t❡❞ ♣❛tt❡r♥s ✭✜❣✉r❡ ✸✳✽✭❜✮✮✳

❚❤❡ ❝♦♠♣❛r✐s♦♥ ♦❢ ✜❣✉r❡ ✸✳✽✭❜✮ ❛♥❞ ✸✳✽✭❝✮ s❤♦✇s t❤❛t t❤❡ ♣❛tt❡r♥ ✐s ❞②♥❛♠✐❝ ❛♥❞

t❤❛t ❛❣❣r❡❣❛t❡s ❝❤❛♥❣❡ ❝♦♥t✐♥✉♦✉s❧② ✐♥ s✐③❡ ❛♥❞ ♣♦s✐t✐♦♥ ❞✉❡ t♦ t❤❡ st♦❝❤❛st✐❝ ❞✐✲

✈✐s✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t ❡✈❡♥ts✳ ❚❤✐s s✐♠✉❧❛t✐♦♥ ✐❧❧✉str❛t❡s ♦♥❡ ♦❢ t❤❡ ❧✐♠✐t❛t✐♦♥ ♦❢

t❤❡ ■❇▼ ❛♣♣r♦❛❝❤✳ ❚❤❡ ❡❝♦❧♦❣✐❝❛❧ s✐❣♥❛❧ ✐s ♦❢t❡♥ ❜❧✉rr❡❞ ❜② st♦❝❤❛st✐❝ ✢✉❝t✉❛t✐♦♥s✳

❚❤✉s ❝❤❡❝❦✐♥❣ t❤❡ ♠♦❞❡❧ ♦r ✐ts ✐♠♣❧❡♠❡♥t❛t✐♦♥ ✐s ❛ ♥♦♥ tr✐✈✐❛❧ t❛s❦✳

❲❡ ✉s❡ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ❛s ❛ ♠❡❛s✉r❡ t♦ ❝❤❛r❛❝t❡r✐③❡ t❤❡ ❛❣❣r❡❣❛t❡❞

♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼✳ ❚❤❡ ❢✉♥❝t✐♦♥✱ ♠❡❛s✉r✐♥❣ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ❜❛❝t❡r✐❛

❧♦❝❛t❡❞ ❛t ❞✐✛❡r❡♥t ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ❢r♦♠ ❛ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧✱ t❛❦❡s t❤❡ ❢♦r♠ ♦❢ ❛

♠❛tr✐①✳ ❚❤❡ ♠❛tr✐① ✐s r❛❞✐❛❧❧② s②♠♠❡tr✐❝ ❛♥❞ t❤❡ ❝❡♥t❡r ♦❢ t❤❡ ♠❛tr✐① ❝♦rr❡s♣♦♥❞ t♦

t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ♥❡✐❣❤❜♦rs ❛t ❛ ❞✐st❛♥❝❡ s♠❛❧❧❡r t❤❛♥ t❤❡ s♣❛t✐❛❧ r❡s♦❧✉t✐♦♥ dξ✳

❋✐❣✉r❡ ✸✳✾ s❤♦✇s t❤❡ r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✭❡①tr❛❝t❡❞ ❢r♦♠ t❤❡ ❝❡♥tr❛❧ r♦✇

♦❢ t❤❡ ❈❛rt❡s✐❛♥ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✮✳ ❆s t❤❡ ✐♥✐t✐❛❧ ❞✐str✐❜✉t✐♦♥ ♦❢ ✐♥❞✐✈✐❞✉❛❧s

✐s ✉♥✐❢♦r♠ t❤❡ ✐♥✐t✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ t❛❦❡s ✈❛❧✉❡s ❝❧♦s❡ t♦ ♦♥❡✳ ❍♦✇❡✈❡r

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✹✽

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

❋✐❣✉r❡ ✸✳✶✵✿ ❚✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ s✐♠✉❧❛t❡❞ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❝❛❧❝✉❧❛t❡❞ ✉s✐♥❣

t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ❛♥❞ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✭✺ r✉♥s✮

✇❤❡♥ ♣❛tt❡r♥ st❛rt t♦ ❢♦r♠✱ t❤❡ ❢✉♥❝t✐♦♥ ♣❡❛❦❡❞ ❛t s♠❛❧❧ ❞✐st❛♥❝❡s ✐♥❞✐❝❛t✐♥❣ t❤❡

❢♦r♠❛t✐♦♥ ♦❢ ❛❣❣r❡❣❛t❡s✳ ❚❤❡ ❢✉♥❝t✐♦♥ r❡❛❝❤❡s ❛ ♣s❡✉❞♦✲st❛t✐♦♥❛r② ✭s❡❡ ✜❣✉r❡ ✸✳✾

t✐♠❡ ❂ 50 ❛♥❞ 90✮ ❛♥❞ ✈❛r② s❧✐❣❤t❧② ❞✉❡ t♦ r❛♥❞♦♠ ✢✉❝t✉❛t✐♦♥s✳

▼♦♠❡♥t ♠♦❞❡❧ ❛tt❡♠♣ts t♦ ❝❛♣t✉r❡ t❤❡ ❞❡t❡r♠✐♥✐st✐❝ ❞②♥❛♠✐❝ ♦❢ t❤❡ ♣❛✐r ❝♦r✲

r❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✳ ❋✐❣✉r❡ ✸✳✶✶ ❝♦♠♣❛r❡s t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ♦❜t❛✐♥❡❞ ❜②

s♦❧✈✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ t❤❡ ■❇▼✳ ❚❤❡ r❡s✉❧ts ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛r❡ ✐♥

❛❝❝♦r❞❛♥❝❡ ✇✐t❤ t❤♦s❡ ♦❢ t❤❡ ■❇▼✳ ❚❤✐s s❤♦✇s t❤❛t t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❝❛♥ ❤❡❧♣

✐♥ ❡①tr❛❝t✐♥❣ t❤❡ ❞❡t❡r♠✐♥✐st✐❝ ❡❝♦❧♦❣✐❝❛❧ ✬s✐❣♥❛❧✬✳ ❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❝❛♣t✉r❡ t❤❡

♠❛✐♥ ❞❡t❡r♠✐♥✐st✐❝ ❢❡❛t✉r❡s ♦❢ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ s✐♠✉❧❛t❡❞ ✇✐t❤ t❤❡ ■❇▼✳

✸✳✷✳✷ ❉❡♥s✐t② ❞❡♣❡♥❞❛♥t ❞✐✈✐s✐♦♥ ♠♦❞❡❧ ✭b′1 > 0✮

■♥ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ ♠♦❞❡❧✱ t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐s r❡✲

❞✉❝❡❞ ❜② t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s✳ ❚❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ✐s t❤❡♥ ❡①♣❡❝t❡❞ t♦ ❤❛✈❡ ❛♥

✐♠♣❛❝t ♦♥ t❤❡ t✐♠❡ ❝♦✉rs❡ ♦❢ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✳ ■♥ ♦r❞❡r t♦ ❛ss❡ss

t❤❡ ✐♠♣❛❝t ♦❢ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥✱ ✇❡ ✉s❡ t❤❡ ♥♦♥ s♣❛t✐❛❧ ♠❡❛♥✲✜❡❧❞ ♠♦❞❡❧ ❛s ❛

r❡❢❡r❡♥❝❡ t♦ ✇❤✐❝❤ ✇❡ ❝♦♠♣❛r❡ t❤❡ r❡s✉❧ts ♦❢ t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❚❤❡

♠❡❛♥✲✜❡❧❞ ❧✐♠✐t ✐s ❣✐✈❡♥ ❜②✿

dN

dt= (b1 − d1)N − b′1N

2 ✭✸✳✶✵✮

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✸✳✸✳ ❉✐s❝✉ss✐♦♥ ✹✾

❋✐❣✉r❡ ✸✳✶✶✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ t♦ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲

❜❛s❡❞ ♠♦❞❡❧✳ ❚❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ r❡s✉❧ts ❛r❡ ❛✈❡r❛❣❡❞ ♦✈❡r ✺ s✐♠✉❧❛t✐♦♥s

❚❤❡ st❛t✐♦♥❛r② s♦❧✉t✐♦♥s ❛r❡ N∗ = 0 ♦r N∗ = (b1 − d1)/b′1✳ ◆♦t❡ t❤❛t ✐❢ b1 = d1

t❤❛♥ N∗ = 0✳ ❋♦r t❤❡ s✐♠✉❧❛t✐♦♥s ✇✐t❤ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦❞❡❧ ✇❡ ❝♦♥s✐❞❡r

t❤❡ ❝❛s❡ ✇❤❡r❡ b1 > d1 ❛♥❞ b′1 > 0✳ ❋✐❣✉r❡ ✸✳✶✶ ❝♦♠♣❛r❡s t❤❡ t✐♠❡ ❝♦✉rs❡ ♦❢ t❤❡

❛✈❡r❛❣❡ ❞❡♥s✐t✐❡s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❢♦r b1 = 0.1✱ d1 = 0.05

❛♥❞ b′1 = 0.2✳ ❚❤❡ ❝♦rr❡s♣♦♥❞✐♥❣ st❛t✐♦♥❛r② s♦❧✉t✐♦♥ ♦❜t❛✐♥❡❞ ✇✐t❤ t❤❡ ♥♦♥ s♣❛t✐❛❧

♠♦❞❡❧ ✐s N∗ = 0.25✳ ❋✐❣✉r❡ ✸✳✶✷ s❤♦✇s t❤❛t ❜♦t❤ t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧s

②✐❡❧❞s ❡q✉✐❧✐❜r✐✉♠ ✈❛❧✉❡s ♦❢ t❤❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❧♦✇❡r t❤❛♥ t❤❛t ②✐❡❧❞❡❞ ❜②

t❤❡ ♥♦♥ s♣❛t✐❛❧ ♠♦❞❡❧✳ ❚❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s r❡❞✉❝❡s t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡

✐♥❞✐✈✐❞✉❛❧s ❝♦♠♣❛r❡❞ t♦ t❤❡ ❝❛s❡ ♦❢ ✉♥✐❢♦r♠ ❞✐str✐❜✉t✐♦♥ ♦❢ ✐♥❞✐✈✐❞✉❛❧s✳

❋✐❣✉r❡ ✸✳✶✸ s❤♦✇s t❤❡ t✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ ❝❡♥tr❛❧ ❡❧❡♠❡♥t ✈❛❧✉❡ ♦❢ t❤❡ ❈❛rt❡s✐❛♥

♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✳ ❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❝❛♣t✉r❡s ✇❡❧❧ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ❧♦❝❛❧

♥❡✐❣❤❜♦r❤♦♦❞ s✐♠✉❧❛t❡❞ ❜② t❤❡ ■❇▼✳

✸✳✸ ❉✐s❝✉ss✐♦♥

❖✉r r❡s✉❧ts ♦♥ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥✲❞❡❛t❤ ♠♦❞❡❧ ❝♦♥✜r♠ t❤❛t ♠♦♠❡♥t

❛♣♣r♦①✐♠❛t✐♦♥ ❝❛♥ ❝❛♣t✉r❡ t❤❡ ❞❡t❡r♠✐♥✐st✐❝ ❛✈❡r❛❣❡ ❜❡❤❛✈✐♦r ♦❢ st♦❝❤❛st✐❝ ■❇▼s✳

■❇▼s ✉s❡❞ ✐♥ ♠✐❝r♦❜✐♦❧♦❣② ❛r❡ ♦❢t❡♥ ❝♦♠♣❧❡① ❛♥❞ ✐♥❝❧✉❞❡ s❡✈❡r❛❧ ❞❡t❛✐❧s ❛❜♦✉t t❤❡

s❤❛♣❡ ❛♥❞ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡② ❝❛♥ ♦♥❧② ❡①♣❧♦r❡❞ ♥✉♠❡r✐❝❛❧❧② ❛♥❞

❛r❡ ❞✐✣❝✉❧t t♦ ❛♣♣r♦①✐♠❛t❡ ✇✐t❤ ❞❡t❡r♠✐♥✐st✐❝ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s✳ ❚❤❡r❡ ❛r❡

❝❡rt❛✐♥❧② r❡s❡❛r❝❤ q✉❡st✐♦♥s t❤❛t r❡q✉✐r❡ s✉❝❤ ❛ ❧❡✈❡❧ ♦❢ ❞❡t❛✐❧s✳ ❋♦r ✐♥st❛♥❝❡ ❞❡t❛✐❧❡❞

■❇▼ ♠❛② ❜❡ ♥❡❡❞❡❞ ❢♦r s✐♠✉❧❛t✐♥❣ t❤❡ ✜♥❡ s❝❛❧❡ str✉❝t✉r❡ ♦❢ ❜✐♦✜❧♠s ❛♥❞ ❝❛❧❝✉❧❛t✐♥❣

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✺✵

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

❋✐❣✉r❡ ✸✳✶✷✿ ❚✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✿ b1 = 0.1✱ b′1 = 0.2

❛♥❞ d1 = 0.05

❋✐❣✉r❡ ✸✳✶✸✿ ❋✐rst ♣♦✐♥t ✭❛t ❞✐st❛♥❝❡ ✵✮ ♦❢ t❤❡ r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✿ b1 =

0.1✱ b′1 = 0.2 ❛♥❞ d1 = 0.05

Page 64: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✸✳✸✳ ❉✐s❝✉ss✐♦♥ ✺✶

♣❤②s✐❝❛❧ ❛♥❞ ♠❡❝❤❛♥✐❝❛❧ ♣r♦♣❡rt✐❡s✳ ❍♦✇❡✈❡r✱ ✐❢ t❤❡ ❢♦❝✉s ✐s ♦♥ ✉♥❞❡rst❛♥❞✐♥❣ ❤♦✇

s♣❛t✐❛❧ ♣❛tt❡r♥s ❛✛❡❝t t❤❡ ❛✈❡r❛❣❡ ♣♦♣✉❧❛t✐♦♥ ❞❡♥s✐t✐❡s ♦❢ ♠✐❝r♦❜✐❛❧ s♣❡❝✐❡s✱ t❤❡

❞❡t❛✐❧❡❞ ■❇▼ ❝❛♥ ❜❡ s✐♠♣❧✐✜❡❞ ✇❤✐❝❤ ②✐❡❧❞s ❧❡ss r❡❛❧✐st✐❝ ✜♥❡ s❝❛❧❡ str✉❝t✉r❡s ❜✉t

tr❛❝t❛❜❧❡ ♠♦❞❡❧s t❤❛t ❝❛♥ ❜❡ ❛♣♣r♦①✐♠❛t❡❞ ✇✐t❤ ♠♦♠❡♥t t❡❝❤♥✐q✉❡s✳

❉❡t❡r♠✐♥✐st✐❝ ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ■❇▼s ❤❛s s❡✈❡r❛❧ ❛❞✈❛♥t❛❣❡s✳ ❋✐rst ✐t ✐s ♦❢t❡♥

❡❛s✐❡r t♦ ❛♥❛❧②③❡ ❛ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ t❤❛♥ ❛ st♦❝❤❛st✐❝ ■❇▼✳ ▼♦♠❡♥t ♠♦❞❡❧s

❛r❡ ♠♦r❡ ❝♦♠♣✉t❛t✐♦♥❛❧❧② ♠♦r❡ ♣❡r❢♦r♠❡♥t t❤❛♥ ■❇▼✳ ❙❡❝♦♥❞ ✐t ✐s ♦❢t❡♥ ❞✐✣❝✉❧t

t♦ ❝❤❡❝❦ t❤❛t ■❇▼s ✐♠♣❧❡♠❡♥t❛t✐♦♥ ✐♥t♦ ❛ ❝♦♠♣✉t❡r ❝♦❞❡ ✐s ❡rr♦r ❢r❡❡✳ ❚❤✉s ❞❡✲

t❡r♠✐♥✐st✐❝ ❛♣♣r♦①✐♠❛t✐♦♥ ♠❛② ♣r♦✈✐❞❡ ❛ r❡❢❡r❡♥❝❡ t♦ ✇❤✐❝❤ t❤❡ ■❇▼ r❡s✉❧ts ❝❛♥ ❜❡

❝♦♠♣❛r❡❞✳ ❚❤✐r❞✱ s❡✈❡r❛❧ q✉❡st✐♦♥s ✇❤✐❝❤ ❛r❡ ✐♠♣♦rt❛♥t ✐♥ ❡❝♦❧♦❣② ❛r❡ ❞✐✣❝✉❧t t♦

❛♥s✇❡r ♦♥ t❤❡ s♦❧❡ ❜❛s✐s ♦❢ st♦❝❤❛st✐❝ s✐♠✉❧❛t✐♦♥✳ ❊①❛♠♣❧❡ ✐♥❝❧✉❞❡s t❤❡ ❝❤❛r❛❝t❡r✐✲

③❛t✐♦♥ ♦❢ t❤❡ ❧♦♥❣✲r✉♥ ♣❛tt❡r♥s ❛♥❞ t❤❡ ✐❞❡♥t✐✜❝❛t✐♦♥ ♦❢ st❛t✐♦♥♥❛r② st❛t❡s✳ ❋✐♥❛❧❧②✱

■❇▼ ♦❢t❡♥ ❤❛✈❡ ❛ ❧❛r❣❡ ♣❛r❛♠❡t❡r st❛t❡ s♣❛❝❡ t❤❛t ❝❛♥ ♦♥❧② ❜❡ s❛♠♣❧❡❞ ❛♥❞ ✐t ✐s

❞✐✣❝✉❧t t♦ ❞❡t❡r♠✐♥❡ t❤❡ ❡✛❡❝t ♦❢ ✈❛r②✐♥❣ ♣❛r❛♠❡t❡rs ♦r ✐♥✐t✐❛❧ ❝♦♥❞✐t✐♦♥s ♦♥ t❤❡

q✉❛❧✐t❛t✐✈❡ ❛♥❞ q✉❛♥t✐t❛t✐✈❡ ♦✉t❝♦♠❡ ♦❢ t❤❡ ■❇▼✳

❚❤❡ r❡❞✉❝t✐♦♥ ♦❢ ❛♥ ■❇▼ t♦ ❛ s♠❛❧❧ s❡t ♦❢ ❡q✉❛t✐♦♥s r❡q✉✐r❡ ❛ ♥✉♠❜❡r ♦❢ ❛♣♣r♦①✐✲

♠❛t✐♦♥✳ ❇✐r❝❤ ❡t ❛❧✳ ❬❇✐r❝❤ ✷✵✵✻❪ s❤♦✇❡❞ t❤❛t ♠♦♠❡♥t ♠❡t❤♦❞s ❛r❡ r❡❞✉❝t✐♦♥s ♦❢ t❤❡

♠❛st❡r ❡q✉❛t✐♦♥✳ ❚❤❡ ♠❛st❡r ❡q✉❛t✐♦♥ ❝♦♥t❛✐♥s ❝♦♠♣❧❡t❡ ❛♥❞ ❞❡t❛✐❧❡❞ ✐♥❢♦r♠❛t✐♦♥

❝♦♥❝❡r♥✐♥❣ ❛❧❧ ♦❢ t❤❡ st❛t✐st✐❝❛❧ ♣r♦♣❡rt✐❡s ♦❢ ❛♥ ■❇▼ ❜✉t ✐t ✐s ♦❢t❡♥ ✈❡r② ❝♦♠♣❧✐❝❛t❡❞

t♦ ❞❡r✐✈❡ ❛♥❞ t♦ s♦❧✈❡✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ✐s ❛♥ ❛❧t❡r♥❛t✐✈❡ ❛♣♣r♦❛❝❤ ❜❛s❡❞ ♦♥

❛♥ ✉♥❝❧♦s❡❞ ❤✐❡r❛r❝❤② ♦❢ s♣❛t✐❛❧ ♠♦♠❡♥ts ❬❇✐r❝❤ ✷✵✵✻❪✳ ▼♦♠❡♥t ♠♦❞❡❧s ❛r❡ ♦❢t❡♥

❧✐♠✐t❡❞ t♦ t❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥ts ❛♥❞ ✉s❡ ❛♣♣r♦①✐♠❛t✐✈❡ ❝❧♦s✉r❡ r❡✲

❧❛t✐♦♥ ❡①♣r❡ss✐♥❣ t❤❡ t❤✐r❞ ♠♦♠❡♥t ❛s ❛ ❢✉♥❝t✐♦♥ ♦❢ t❤❡ s❡❝♦♥❞ ❛♥❞ ✜rst ♠♦♠❡♥ts✳

❚❤❡ ❝❧♦s✉r❡ ❡①♣r❡ss✐♦♥ ✐♠♣❧✐❡s t❤❛t t❤❡ ♣♦s✐t✐♦♥s ♦❢ tr✐♣❧❡t ❛♥❞ ❤✐❣❤❡r ♥✉♠❜❡r ♦❢

✐♥❞✐✈✐❞✉❛❧s ❛r❡ ♥♦t ❝♦rr❡❧❛t❡❞✳ ❚❤✐s ✐s ❛♥ ❛♣♣r♦①✐♠❛t✐♦♥ t❤❛t ♥❡❡❞ t♦ ❜❡ ❛ss❡ss❡❞

❜② ❝♦♠♣❛r✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ t♦ t❤❡ ■❇▼ s✐♠✉❧❛t✐♦♥✳

❆♥♦t❤❡r ✐♠♣♦rt❛♥t ❛♣♣r♦①✐♠❛t✐♦♥ r❡❧✐❡s ♦♥ t❤❡ ✉s❡✱ ✐♥ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✱ ♦❢ t❤❡

❛✈❡r❛❣❡ ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ■♥ ♠♦♠❡♥t ♠♦❞❡❧s t❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧

❡♥✈✐r♦♥♠❡♥t ✐s ♦❢t❡♥ ❡①♣r❡ss❡❞ ✇✐t❤ t❤❡ ✐♥t❡❣r❛❧ ♦❢ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❞❡♥s✐t✐❡s

✇❡✐❣❤t❡❞ ✇✐t❤ ❛♥ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧✿

K

(

||ξ||

wd

)

C(ξ)dξ ✭✸✳✶✶✮

❍♦✇❡✈❡r ✐♥ t❤❡ ■❇▼ t❤❡ ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐s ✈❛r✐❛❜❧❡✳ ❚❤✉s ✐❢

t❤❡ ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ✈❛r✐❡s ✇✐t❤✐♥ ❛ ✇✐❞❡ r❛♥❣❡ ✐♥❞✐✈✐❞✉❛❧s ♠❛② ❡①♣❡r✐❡♥❝❡ ❧♦❝❛❧

❞❡♥s✐t✐❡s t❤❛t ❛r❡ ✈❡r② ❞✐✛❡r❡♥t ❢r♦♠ t❤❡ ❛✈❡r❛❣❡✳ ❚❤✐s ♠❛② ❝❛✉s❡ t❤❡ ❢❛✐❧✉r❡ ♦❢ t❤❡

♠♦♠❡♥t ♠♦❞❡❧ ✐♥ ❝❛♣t✉r✐♥❣ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ❞②♥❛♠✐❝ ❛s ✇✐❧❧ ❜❡ ✐❧❧✉str❛t❡❞ ✐♥

❝❤❛♣t❡r ✻

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✺✷

❈❤❛♣t❡r ✸✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ ■❇▼ ❢♦r ❝♦❧♦♥②

❣r♦✇t❤

❋✐♥❛❧❧②✱ t❤❡ ❛ss❡ss♠❡♥t ♦❢ t❤❡ q✉❛❧✐t② ♦❢ t❤❡ ❛♣♣r♦①✐♠❛t✐♦♥ ♠❛❞❡ ✐♥ t❤❡ ♠♦♠❡♥t

♠♦❞❡❧ ❛r❡ ♦❢t❡♥ ♣❡r❢♦r♠❡❞ ❜② ❝♦♠♣❛r✐♥❣ t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ s✐♠✉❧❛✲

t✐♦♥s✳ ❚❤❡ s✐♠✉❧❛t✐♦♥s ❛r❡ r✉♥ ❢♦r ♣❛rt✐❝✉❧❛r s❡t ♦❢ ♣❛r❛♠❡t❡rs ❛♥❞ ✐t ✐s ♥♦t ❝❧❡❛r

✇❤❡t❤❡r ❛ ❝♦♠♣❛r✐s♦♥ ♦❢ t❤❡ r❡s✉❧ts ♦✈❡r ❛ s♠❛❧❧ s❡t ♦❢ ♣❛r❛♠❡t❡rs ✐s s✉✣❝✐❡♥t t♦

❛ss❡ss t❤❡ q✉❛❧✐t② ♦❢ t❤❡ ❛♣♣r♦①✐♠❛t✐♦♥✳

✸✳✹ ❆♥♥❡①❡ ❆✿ ❡①♣r❡ss✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✐♥ r❛❞✐❛❧

❝♦♦r❞✐♥❛t❡s

❙♦❧✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦♠❡♥t ✐♥✈♦❧✈❡s t❤❡ ❝❛❧❝✉❧❛t✐♦♥ ♦❢ t✇♦✲

❞✐♠❡♥s✐♦♥❛❧ ❝♦♥✈♦❧✉t✐♦♥s ❤❛✈✐♥❣ t❤❡ ❢♦❧❧♦✇✐♥❣ ❢♦r♠✿

(C ⋆m)(ξ) =

ξ′C(ξ + ξ′)m(ξ′)dξ′ ✭✸✳✶✷✮

❆s ξ ❛♥❞ ξ′ ❛r❡ ❞❡✜♥❡❞ ❛s ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡s ✇❤✐❝❤✱ ✇❤❡♥ ❡①♣r❡ss❡❞ ✐♥ ❈❛rt❡s✐❛♥

❝♦♦r❞✐♥❛t❡s ✇r✐t❡ ✿ ξ = (ξ1, ξ2) ❛♥❞ ξ′ = (ξ′1, ξ′2)✮✱ t❤❡ ✐♥t❡❣r❛❧ ♦✈❡r t❤❡ ξ

′ ✐s ❛ ❞♦✉❜❧❡✲

✐♥t❡❣r❛❧✿

(C ⋆m)(ξ1, ξ2) =

ξ′1

ξ′2

C(ξ1 + ξ′1, ξ2 + ξ′2)m(ξ′1, ξ′2)dξ

′1dξ

′2 ✭✸✳✶✸✮

❚❤❡ ❝♦♥✈♦❧✉t✐♦♥ ❝❛♥ ❜❡ ❛❧s♦ ❡①♣r❡ss❡❞ ✐♥ ♣♦❧❛r ❝♦♦r❞✐♥❛t❡s ❛s✿

(C ⋆m)(r) =

r′

θC(r′)m(R(r, r′, θ))r′dr′dθ ✭✸✳✶✹✮

✇❤❡r❡ R(r, r′, θ) = (r2 + r′2 − 2rr′ cos θ)1/2

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❈❤❛♣t❡r ✹

▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛

s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤

❞❡t❛❝❤♠❡♥t

❈♦♥t❡♥ts

✹✳✶ ■♥tr♦❞✉❝t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✸

✹✳✷ ❆ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤ ❞❡t❛❝❤♠❡♥t ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✹

✹✳✷✳✶ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✻

✹✳✸ ■❇▼ s✐♠✉❧❛t✐♦♥ r❡s✉❧ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✻

✹✳✹ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✺✼

✹✳✺ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ t❤❡ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✶

✹✳✻ ❉✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✷

✹✳✶ ■♥tr♦❞✉❝t✐♦♥

■♥ t❤✐s ❝❤❛♣t❡r ✇❡ ♣r♦♣♦s❡ t♦ ❞❡r✐✈❡ ❛ ♠♦♠❡♥t ♠♦❞❡❧ ❛♣♣r♦①✐♠❛t✐♥❣ ❛ s✐♠♣❧✐✜❡❞

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✭■❇▼✮ ♦❢ ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠s ❞❡✈❡❧♦♣♠❡♥t✳ ❚❤❡ ■❇▼ ✐s ❜❛s✐✲

❝❛❧❧② ❛♥ ❡①t❡♥s✐♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ❣r♦✇t❤ ■❇▼ ♣r❡s❡♥t❡❞ ✐♥ ❝❤❛♣t❡r ✸ ❜② ❝♦♥s✐❞❡r✐♥❣ ❛

♠✉❧t✐✲❝♦❧♦♥✐❡s s②st❡♠ ❛♥❞ ✐♥❝❧✉❞✐♥❣ ❛ ❜✐♦✜❧♠ ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss✳ ❖✉r ❛✐♠ ✐s ✜rst

t♦ ❡①♣❧♦r❡ t❤❡ ❞✐✛❡r❡♥t s♣❛t✐❛❧ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ✉♥❞❡r ❞✐✛❡r❡♥t ❞✐✈✐✲

s✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t ❝♦♥❞✐t✐♦♥s✳ ❲❡ ❝❤❛r❛❝t❡r✐③❡ t❤❡s❡ ♣❛tt❡r♥s ✉s✐♥❣ t❤❡ ✜rst ❛♥❞

s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥ts ✐♥tr♦❞✉❝❡❞ ✐♥ t❤❡ ♣r❡✈✐♦✉s ❝❤❛♣t❡r✳ ❙❡❝♦♥❞✱ ✇❡ ♣r♦♣♦s❡ t♦

❛♣♣r♦①✐♠❛t❡ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡s❡ ❛❣❣r❡❣❛t❡❞ ❞❡s❝r✐♣t♦rs ✉s✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✲

✐♠❛t✐♦♥ ❛♣♣r♦❛❝❤ ❛♥❞ ❝♦♠♣❛r❡ t❤❡ r❡s✉❧t ♦❢ t❤❡ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦♠❡♥t

♠♦❞❡❧ t♦ t❤❡ ■❇▼ s✐♠✉❧❛t✐♦♥s✳

❚❤❡ ❝❤❛♣t❡r ✐s ♦r❣❛♥✐③❡❞ ✐♥ ❢♦✉r s❡❝t✐♦♥s✳ ❚❤❡ ✜rst s❡❝t✐♦♥ ✐s ❞❡❞✐❝❛t❡❞ t♦ t❤❡

❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✇❤❡r❡ t❤❡ ✐♥❞✐✈✐❞✉❛❧s

❛r❡ s✉❜❥❡❝t t♦ ❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss✳ ■♥ t❤❡ s❡❝♦♥❞ s❡❝t✐♦♥ ✇❡

♣r♦♣♦s❡ t♦ ❡①♣❧♦r❡ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ✇❤❡♥ t❤❡ s♣❛t✐❛❧ r❛♥❣❡s ♦❢

t❤❡ ❞✐✈✐s✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧s ❛r❡ ✈❛r✐❡❞✳ ❲❡ ❞❡r✐✈❡ ❛ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥

♠♦❞❡❧ ✐♥ t❤❡ t❤✐r❞ s❡❝t✐♦♥ ♦❢ t❤❡ ❝❤❛♣t❡r✳ ❋✐♥❛❧❧② ✇❡ ❝♦♠♣❛r❡ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧

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✺✹

❈❤❛♣t❡r ✹✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤

❞❡t❛❝❤♠❡♥t

❋✐❣✉r❡ ✹✳✶✿ ❚❤❡ s♣❛t✐❛❧ str✉❝t✉r❡ ✐♥ ❛ ❞❡✈❡❧♦♣✐♥❣ ❜✐♦✜❧♠ ❛s r❡✈❡❛❧❡❞ ❜② ❛❞✈❛♥❝❡❞

♠✐❝r♦s❝♦♣② t❡❝❤♥✐q✉❡s ✭❈❙▲▼✮ ❬❚♦❧❦❡r✲◆✐❡❧s❡♥ ✷✵✵✵❪✳ ❚❤❡ ✐♥✐t✐❛❧ ♣❛tt❡r♥ ❢♦r♠❡❞

✇✐t❤ ❛ s♠❛❧❧ ♥✉♠❜❡r ♦❢ ❝❡❧❧s ❛❞s♦r❜❡❞ ♦♥ ❛ s✉r❢❛❝❡ ✭❧❡❢t✮ ❡✈♦❧✈❡s t♦✇❛r❞ ❛ ♠✉❧t✐✲

❝♦❧♦♥✐❡s ♣❛tt❡r♥ ✭♠✐❞❞❧❡ ❛♥❞ r✐❣❤t✮

❛♥❞ t❤❡ ■❇▼ ✐♥ t❤❡ ❢♦✉rt❤ s❡❝t✐♦♥ ❛♥❞ ❛ss❡ss t❤❡ ❝❛♣❛❝✐t② ♦❢ t❤❡ ❛❣❣r❡❣❛t❡❞ ♠♦❞❡❧

✐♥ r❡♣r♦❞✉❝✐♥❣ t❤❡ ♠❛✐♥ ❢❡❛t✉r❡s ♦❢ t❤❡ s✐♠✉❧❛t❡❞ ♣❛tt❡r♥s✳

✹✳✷ ❆ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤ ❞❡t❛❝❤♠❡♥t

❇❛❝t❡r✐❛ ❛tt❛❝❤ t♦ ❤②❞r❛t❡❞ s✉r❢❛❝❡s ❛♥❞ ❞❡✈❡❧♦♣ ❜✐♦✜❧♠s✳ ❇✐♦✜❧♠s ❞❡✈❡❧♦♣♠❡♥t

✐s ❛ ❝♦♠♣❧❡① ❛♥❞ s❡q✉❡♥t✐❛❧ ♣r♦❝❡ss ♦❢t❡♥ ✐♥✐t✐❛t❡❞ ❜② t❤❡ ❛❞s♦r♣t✐♦♥ ♦❢ ❛ s♠❛❧❧ ♥✉♠✲

❜❡r ♦❢ ❝❡❧❧s ♦♥ ❛ s✉r❢❛❝❡✳ ❚❤r♦✉❣❤ ❜✐♥❛r② ✜ss✐♦♥ ❛♥❞ ❛ ♥✉♠❜❡r ♦❢ ♦t❤❡r ♠❡❝❤❛♥✐s♠s

✐♥❝❧✉❞✐♥❣ s✉r❢❛❝❡ ♠✐❣r❛t✐♦♥✱ ❡①♦♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t t❤❡ ✐♥✐t✐❛❧ ❝♦❧♦✲

♥✐③❡rs ❞❡✈❡❧♦♣ ♣r♦❣r❡ss✐✈❡❧② ❝♦♠♣❧❡① ❛♥❞ s♦♣❤✐st✐❝❛t❡❞ str✉❝t✉r❡s✳ ❋✐❣✉r❡ ✹✳✶ s❤♦✇s

❛♥ ❡①❛♠♣❧❡ ♦❢ ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t ♣r♦❝❡ss ✭✉♥❞❡r s♣❡❝✐✜❝ ❧❛❜♦r❛t♦r② ❝♦♥❞✐t✐♦♥s✮

✇❤❡r❡ ❛ s♠❛❧❧ ♥✉♠❜❡r ♦❢ ❝❡❧❧s ❞❡✈❡❧♦♣ ✐♥t♦ ❛ ♠✉❧t✐✲❝♦❧♦♥✐❡s ❜✐♦✜❧♠✳

❚❤❡ ❛❝❝✉♠✉❧❛t✐♦♥ ♦❢ t❤❡ ♠✐❝r♦♦r❣❛♥✐s♠s ♦♥ t❤❡ ❝♦❧♦♥✐③❡❞ s✉r❢❛❝❡ ♠❛② ❜❡ r❡✲

str✐❝t❡❞ ❜② ♥✉tr✐❡♥t ❛✈❛✐❧❛❜✐❧✐t② ✭tr❡❛t❡❞ ✐♥ ❝❤❛♣t❡r ✷ ❛♥❞ ✸✮ ❛♥❞✴♦r ❝♦✉♥t❡r❜❛❧✲

❛♥❝❡❞ ❜② t❤❡ ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss✳ ❚❤❡ t❡r♠ ❞❡t❛❝❤♠❡♥t ❤❡r❡ r❡❢❡rs t♦ ❞✐✛❡r✲

❡♥t ♠❡❝❤❛♥✐s♠s ❜② ✇❤✐❝❤ ❜❛❝t❡r✐❛❧ ♣❛rt✐❝❧❡s ❛r❡ tr❛♥s♣♦rt❡❞ ❢r♦♠ t❤❡ ✭❛tt❛❝❤❡❞✮

❜✐♦✜❧♠ t♦ t❤❡ s✉rr♦✉♥❞✐♥❣ ✢✉✐❞ ♣❤❛s❡✳ ❉✐✛❡r❡♥t ♣r♦❝❡ss❡s ❛r❡ r❡s♣♦♥s✐❜❧❡ ❢♦r

❞❡t❛❝❤♠❡♥t ♦❢ ❜✐♦♠❛ss ❢r♦♠ ❜✐♦✜❧♠s ❛♥❞ ❢♦✉r ❝❛t❡❣♦r✐❡s ❝❛♥ ❜❡ ❞✐st✐♥❣✉✐s❤❡❞

❬▼♦r❣❡♥r♦t❤ ✷✵✵✵❪❬❙t❡✇❛rt ✶✾✾✸❪✿ ✭✶✮ ❛❜r❛s✐♦♥✱ ✭✷✮ ❡r♦s✐♦♥✱ ✭✸✮ s❧♦✉❣❤✐♥❣ ❛♥❞ ✭✹✮

♣r❡❞❛t♦r ❣r❛③✐♥❣✳ ❆❜r❛s✐♦♥ ❛♥❞ ❡r♦s✐♦♥ ❜♦t❤ r❡❢❡r t♦ t❤❡ r❡♠♦✈❛❧ ♦❢ s♠❛❧❧ ❣r♦✉♣s

♦❢ ❝❡❧❧s ❢r♦♠ t❤❡ s✉r❢❛❝❡ ♦❢ t❤❡ ❜✐♦✜❧♠ ✇❤✐❧❡ s❧♦✉❣❤✐♥❣ r❡❢❡rs t♦ t❤❡ ❞❡t❛❝❤♠❡♥t ♦❢

r❡❧❛t✐✈❡❧② ❧❛r❣❡ ♣♦rt✐♦♥s ♦❢ t❤❡ ❜✐♦✜❧♠ ❬▼♦r❣❡♥r♦t❤ ✷✵✵✵❪✳

■♥ t❤✐s s❡❝t✐♦♥ ✇❡ ❞❡s❝r✐❜❡ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢ ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t ✉♥❞❡r ❞✐✛❡r❡♥t

❣r♦✇t❤ ❛♥❞ ❞❡t❛❝❤♠❡♥t ❝♦♥❞✐t✐♦♥s✳ ❚❤❡ ♠♦❞❡❧ ✐s ❜❛s✐❝❛❧❧② ❛♥ ❡①t❡♥s✐♦♥ ♦❢ t❤❡ ■❇▼

t❤❛t ✇❡ ♣r❡s❡♥t❡❞ ✐♥ ❝❤❛♣t❡r ✸ ✇✐t❤ t❤❡ ❢♦❧❧♦✇✐♥❣ t❤r❡❡ ♠♦❞✐✜❝❛t✐♦♥s✿

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✹✳✷✳ ❆ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤ ❞❡t❛❝❤♠❡♥t ✺✺

• ✇❡ ❛ss✉♠❡ t❤❛t t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐s ❜❛❧❛♥❝❡❞ ❡①❝❧✉s✐✈❡❧② ❜②

t❤❡ ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss r❛t❤❡r t❤❛♥ ❜② t❤❡ ❝♦♠♣❡t✐t✐♦♥ ♦♥ t❤❡ ♥✉tr✐❡♥t✳ ❚❤✉s

✐♥ t❤✐s ♠♦❞❡❧ ✇❡ ❛ss✉♠❡ t❤❛t ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❧♦❝❛t❡❞ ✐♥ x = (x1, x2) ❞✐✈✐❞❡s ❛t ❛

❝♦♥st❛♥t ♣r♦❜❛❜✐❧✐t② r❛t❡ b1✳ ❚❤❡ ♣r♦❜❛❜✐❧✐t② t❤❛t t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ x ♣r♦❞✉❝❡s

❛ ♥❡✇ ❜♦r♥ ❧♦❝❛t❡❞ ✐♥ x′ ✐s ❣✐✈❡♥ ❜②✿

B(x, x′) = b1K

(

||x− x′||

wb

)

✭✹✳✶✮

✇❤❡r❡ K(||x − x′||/wb) ✐s ❛ ❜✐rt❤ ❦❡r♥❡❧✳ ❆s ✐♥ ❝❤❛♣t❡r ✸ ✇❡ ❝♦♥s✐❞❡r ❢♦r

s✐♠♣❧✐❝✐t② ❛ ✉♥✐❢♦r♠ ❦❡r♥❡❧ ❞❡✜♥❡❞ ❜②✿

K

(

||x− x′||

wb

)

=

{

1/wb ✐❢ ||x− x′|| < wb

0 ❡❧s❡✭✹✳✷✮

• ✇❡ ♠♦❞❡❧ t❤❡ ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss ❛s ❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣r♦❝❡ss ✇❤❡r❡ t❤❡

r❡♠♦✈❛❧ ♣r♦❜❛❜✐❧✐t② D(x) ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❧♦❝❛t❡❞ ✐♥ x ✐♥❝r❡❛s❡s ✇✐t❤ t❤❡

✐♥❝r❡❛s❡ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡ r❡♠♦✈❛❧ ♣r♦❜❛❜✐❧✐t② D(x) ✐s

❣✐✈❡♥ ❜②✿

D(x) = d1 + d′1ploc(x,wd) ✭✹✳✸✮

d1 ✐s ❛ ❝♦♥st❛♥t ❞❡❛t❤ r❛t❡ ❛♥❞ d′1 ✐s t❤❡ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡✳

ploc(x,wd) ❞❡♥♦t❡s t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐♥ x ❝❛❧❝✉❧❛t❡❞ ✉s✐♥❣ ❛

✉♥✐❢♦r♠ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧K(||x−x′||/wd) ✇✐t❤ s✐③❡ wd✳ ❚❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧

♠❡❛s✉r❡s ❤♦✇ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ x ♣❡r❝❡✐✈❡s t❤❡ ❡✛❡❝t ♦❢ ❛ ♥❡✐❣❤❜♦r ✐♥❞✐✈✐❞✉❛❧

❧♦❝❛t❡❞ ✐♥ x′✳ ❲❡ ♦❜t❛✐♥ t❤❡ ❧♦❝❛❧ ♣❡r❝❡✐✈❡❞ ❞❡♥s✐t② ✐❢ x ❜② s✉♠♠✐♥❣ t❤❡ ❡✛❡❝t

♦❢ ❛❧❧ t❤❡ ♥❡✐❣❤❜♦rs✿

ploc(x,wd) =

N∑

i=1

K

(

||x− xi||

wd

)

✭✹✳✹✮

❚❤❡ ❜✐rt❤ ❦❡r♥❡❧ ♠❡❛s✉r❡s t❤❡ ✐♥st❛♥t❛♥❡♦✉s ❞✐s♣❡rs✐♦♥ ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧ ❛t

❛ ❝❡rt❛✐♥ ❞✐st❛♥❝❡ ❢r♦♠ t❤❡ ❧♦❝❛t✐♦♥ ♦❢ t❤❡ ♠♦t❤❡r ❝❡❧❧✳ ❚❛❦✐♥❣ ❧❛r❣❡ ❜✐rt❤ ❦❡r♥❡❧s

✇♦✉❧❞ ②✐❡❧❞ ❛ r❛♣✐❞ ❡①t❡♥s✐♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ❜❡❝❛✉s❡ t❤❡ ♥❡✇❧② ❞✐✈✐❞❡❞ ❝❡❧❧s ❞✐s♣❡rs❡

♦✈❡r ❧❛r❣❡ ❞✐st❛♥❝❡s✳ ❋♦r ❞❡t❛❝❤♠❡♥t✱ ❛ s♠❛❧❧ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ ❝❛♥ ❜❡ ❝♦♥s✐❞❡r❡❞

❛s ❛ ♣r♦①② t♦ ♠♦❞❡❧ s♠❛❧❧ ❜✐♦✜❧♠ ❢r❛❣♠❡♥t ❞❡t❛❝❤♠❡♥t ❛s ✐♥❞✐✈✐❞✉❛❧s s❡♣❛r❛t❡❞

✇✐t❤ ❛ s❤♦rt ❞✐st❛♥❝❡ ✭✇✐t❤ t❤❡ ♦r❞❡r ♦❢ t❤❡ r❛❞✐✐ ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧✮ ❛r❡

❧✐❦❡❧② t♦ ❡①♣❡r✐❡♥❝❡ t❤❡ s❛♠❡ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ploc ❛♥❞ ✇♦✉❧❞ ❞❡t❛❝❤ ✇✐t❤ t❤❡ s❛♠❡

♣r♦❜❛❜✐❧✐t②✳

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✺✻

❈❤❛♣t❡r ✹✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤

❞❡t❛❝❤♠❡♥t

P❛r❛♠❡t❡rs ❉❡s❝r✐♣t✐♦♥ ❱❛❧✉❡

L ❉♦♠❛✐♥ s✐③❡ 201× 201

∆L ❙♣❛t✐❛❧ ❞✐s❝r❡t✐③❛t✐♦♥ 1

b1 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥ r❛t❡ 0.12

d1 ❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡ 0.02

d′1 ❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡ 0.4

wb ❙✐③❡ ♦❢ t❤❡ ❜✐rt❤ ❦❡r♥❡❧ ✈❛r✐❛❜❧❡

wd ❙✐③❡ ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ ✈❛r✐❛❜❧❡

❚❛❜❧❡ ✹✳✶✿ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs

❚❤❡ ❛ss✉♠♣t✐♦♥ t❤❛t t❤❡ ❜✐♦✜❧♠ ❞❡t❛❝❤♠❡♥t ♣r♦❜❛❜✐❧✐t② ✭♦r r❛t❡✮ ✐♥❝r❡❛s❡s ✇✐t❤

t❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✭♦r ❜✐♦✜❧♠ t❤✐❝❦♥❡ss ✐♥ s♦♠❡ ♠♦❞❡❧s✮

✐s ❡♥❝♦✉♥t❡r❡❞ ✐♥ ♠❛♥② ❜✐♦✜❧♠ ❞❡t❛❝❤♠❡♥t ♠♦❞❡❧s✳ ■♠♣❧✐❝✐t❧② ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡

❜✐♦✜❧♠ ❞❡t❛❝❤♠❡♥t r❛t❡ ✐♥❝r❡❛s❡s ✇❤❡♥ t❤❡ ❜✐♦✜❧♠ ❣r♦✇s ✐♥ t❤❡ ✈❡rt✐❝❛❧ ❞✐♠❡♥s✐♦♥

✭t❤♦✉❣❤ ♥♦t ❝♦♥s✐❞❡r❡❞ ❡①♣❧✐❝✐t✐❧② ✐♥ t❤✐s ♠♦❞❡❧✮ ❞✉❡ t♦ ❛♥ ✐♥❝r❡❛s❡❞ ❤②❞r♦❞②♥❛♠✐❝

s❤❡❛r str❡ss✳

❚❤❡ ❝❤♦✐❝❡ ♦❢ t❤❡ ❜✐rt❤ ❛♥❞ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧s ♠❛② ❤❛✈❡ ❛♥ ❡✛❡❝t ♦♥ t❤❡ s②st❡♠

❞②♥❛♠✐❝s ❬❍❡r♥à♥❞❡③✲●❛r❝✐à ✷✵✵✹❪❬❇✐r❝❤ ✷✵✵✻❪✳ ❲✐t❤ r❡❣❛r❞ t♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

♣r♦❝❡ss❡s✱ t❤❡ ✉s❡ ♦❢ ❛ ✉♥✐❢♦r♠ ❦❡r♥❡❧ ❡♠❜♦❞✐❡s t❤❡ ❛ss✉♠♣t✐♦♥ t❤❛t ❛❧❧ t❤❡ ✐♥❞✐✲

✈✐❞✉❛❧s ✇✐t❤✐♥ t❤❡ ❦❡r♥❡❧ ✇✐♥❞♦✇ ❤❛✈❡ ❛♥ ❡q✉❛❧ ❡✛❡❝t ♦♥ t❤❡ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧✳ ❆

●❛✉ss✐❛♥ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ ✇♦✉❧❞ ❣✐✈❡ ❛ ❤✐❣❤❡r ✇❡✐❣❤t t♦ t❤❡ ❝❧♦s❡st ♥❡✐❣❤❜♦rs✳ ❚❤✐s

♠❛② ❤❛✈❡ ❛♥ ❡✛❡❝t ♦♥ t❤❡ ♦❜s❡r✈❡❞ ♣❛tt❡r♥s ❛♥❞ ♦♥ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ♣♦♣✉❧❛t✐♦♥

❞❡♥s✐t②✳ ❲❡ ❞✐s❝✉ss t❤✐s ❜r✐❡✢② ✐♥ t❤❡ ❧❛st s❡❝t✐♦♥ ♦❢ t❤✐s ♣❛♣❡r✳

✹✳✷✳✶ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs

❚❤❡ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs ❛r❡ s✉♠♠❛r✐③❡❞ ✐♥ t❛❜❧❡ ✹✳✷✳✶✳

✹✳✸ ■❇▼ s✐♠✉❧❛t✐♦♥ r❡s✉❧ts

❚♦ ❡①♣❧♦r❡ t❤❡ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❞❡s❝r✐❜❡❞ ❛❜♦✈❡ ✇❡ st❛rt ❜② ❝♦♥s✐❞❡r✲

✐♥❣ t❤❡ ♠❡❛♥✲✜❡❧❞ ❧✐♠✐t✳ ■♥ t❤✐s ❝❛s❡✱ ❛❧❧ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❡①♣❡r✐❡♥❝❡ t❤❡ s❛♠❡ ❛✈❡r❛❣❡

❝♦♥❞✐t✐♦♥s✳ ❚❤✐s ❧✐♠✐t ✐s ♦❜t❛✐♥❡❞ ❜② s❡tt✐♥❣ t❤❡ ❜✐rt❤ ❛♥❞ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ s✐③❡s

t♦ r❡❧❛t✐✈❡❧② ❧❛r❣❡ ✈❛❧✉❡s✳ ❆ ❧❛r❣❡ ❜✐rt❤ ❦❡r♥❡❧ ✇♦✉❧❞ ♠❡❛♥ t❤❛t t❤❡ ✐♥❞✐✈✐❞✉❛❧s

❞✐✈✐❞❡ ❛♥❞ ❞✐s♣❡rs❡ ✐♥st❛♥t❛♥❡♦✉s❧② ♦✈❡r ❛ ❧❛r❣❡ ❞✐st❛♥❝❡✳ ❚❤✐s t❡♥❞s t♦ ♣r❡✈❡♥t t❤❡

❢♦r♠❛t✐♦♥ ♦❢ ❛❣❣r❡❣❛t❡s✳ ❙t❛rt✐♥❣ ❢r♦♠ t❤✐s ❝❛s❡✱ ✇❡ ♣r♦❣r❡ss✐✈❡❧② r❡❞✉❝❡ t❤❡ s✐③❡

♦❢ t❤❡ ❜✐rt❤ ❦❡r♥❡❧ ❛♥❞ ❡①♣❧♦r❡ t❤❡ ❡✛❡❝t ♦♥ t❤❡ ❡♠❡r❣❡♥t s♣❛t✐❛❧ ♣❛tt❡r♥✳ ❋✐❣✉r❡

✹✳✷ s❤♦✇s t❤❡ ✭q✉❛s✐✮ st❛t✐♦♥❛r② s♣❛t✐❛❧ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❢♦r ❛ ❧❛r❣❡

❜✐rt❤ ❦❡r♥❡❧ ✭wb = 19✮ ❛♥❞ ❞✐✛❡r❡♥t s✐③❡s ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ ✭wd = 3 ❛♥❞

wd = 19✮✳ ❆ ❧❛r❣❡ ✈❛❧✉❡ ♦❢ t❤❡ ❜✐rt❤ ❦❡r♥❡❧ s❡❡♠s t♦ ♣r❡✈❡♥t ❝♦❧♦♥② ❢♦r♠❛t✐♦♥ ②✐❡❧❞✲

✐♥❣ ❛ P♦✐ss♦♥✲❧✐❦❡ ♣❛tt❡r♥ ✇❤❡r❡ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛r❡ ✉♥✐❢♦r♠❧② ❞✐str✐❜✉t❡❞ ♦✈❡r t❤❡

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✹✳✹✳ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✺✼

❞♦♠❛✐♥✳ ❍♦✇❡✈❡r✱ ❢♦r s♠❛❧❧ ❜✐rt❤ ❦❡r♥❡❧s ✭✜❣✉r❡ ✹✳✸✮ ✇❡ ♦❜s❡r✈❡ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢

❝♦❧♦♥✐❡s s♣❛❝❡❞ ✇✐t❤ ❛ r❡❣✉❧❛r ❞✐st❛♥❝❡✳ ❚❤❡ ❞✐st❛♥❝❡ ❜❡t✇❡❡♥ t❤❡ ❝♦❧♦♥✐❡s ❝♦rr❡✲

s♣♦♥❞s ❛♣♣r♦①✐♠❛t✐✈❡❧② t♦ t❤❡ r❛❞✐✐ ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ ❛s ✐❧❧✉str❛t❡❞ ✐♥ ✜❣✉r❡

✹✳✹ s❤♦✇✐♥❣ t❤❡ st❛t✐♦♥❛r② ♣❛tt❡r♥s ❢♦r ❛ s♠❛❧❧ ❜✐rt❤ ❦❡r♥❡❧ wb = 3 ❛♥❞ t✇♦ ❞✐✛❡r❡♥t

❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧s wd = 19 ❛♥❞ wd = 31✳ ❚❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ s✐③❡ ♦❢ t❤❡ ❞❡t❛❝❤✲

♠❡♥t ❦❡r♥❡❧ ✐♥❞✉❝❡❞ ❛♥ ✐♥❝r❡❛s❡ ✐♥ t❤❡ s♣❛❝✐♥❣ ❜❡t✇❡❡♥ t❤❡ ❝♦❧♦♥✐❡s✳ ❚❤❡ ♣❛tt❡r♥

♦❢ ✐s♦❧❛t❡❞ ❝♦❧♦♥✐❡s ✐♥ ✜❣✉r❡ ✹✳✹ ✐s ❛ t②♣✐❝❛❧ ❡①❛♠♣❧❡ ♦❢ ❛ s②st❡♠✲❧❡✈❡❧ ❜❡❤❛✈✐♦r t❤❛t

❡♠❡r❣❡s ♦✉t ♦❢ t❤❡ ❧♦❝❛❧ ✐♥t❡r❛❝t✐♦♥s✳ ❚❤❡ ♣❛tt❡r♥ ♠✐♥✐♠✐③❡s t❤❡ ❝♦♠♣❡t✐t✐♦♥ ❜❡✲

t✇❡❡♥ t❤❡ ❝♦❧♦♥✐❡s ✇✐t❤ r❡❣❛r❞ t♦ ❞❡t❛❝❤♠❡♥t✳ ■❢ t❤❡ ❝♦❧♦♥✐❡s ✇❡r❡ t♦♦ ❝❧♦s❡ t♦ ❡❛❝❤

♦t❤❡r✱ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐♥ ❡❛❝❤ ❝♦❧♦♥② ✇♦✉❧❞ ❡①♣❡r✐❡♥❝❡ ❛ ❤✐❣❤❡r ❧♦❝❛❧ ❞❡♥s✐t② t❤❛♥

t❤❡ ❧♦❝❛❧ ❞❡♥s✐t✐❡s ❡①♣❡r✐❡♥❝❡❞ ✐❢ t❤❡ ❝♦❧♦♥✐❡s ✇❡r❡ ✐s♦❧❛t❡❞✳ ❇② ❦❡❡♣✐♥❣ ❛ ❞✐st❛♥❝❡

❜❡t✇❡❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❝♦rr❡s♣♦♥❞✐♥❣ ❛♣♣r♦①✐♠❛t✐✈❡❧② t♦ t❤❡ r❛❞✐✐ ♦❢ t❤❡ ❞❡t❛❝❤✲

♠❡♥t ❦❡r♥❡❧✱ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✇✐t❤✐♥ ❡❛❝❤ ❝♦❧♦♥② ❡①♣❡r✐❡♥❝❡ ♦♥❧② t❤❡ ❡✛❡❝t ♦❢ t❤❡✐r

♥❡✐❣❤❜♦rs ✐♥ t❤❡ ❝♦❧♦♥②✳

✹✳✹ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧

❲❡ ♣r♦♣♦s❡ t♦ ❛♣♣r♦①✐♠❛t❡ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞

t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✉s✐♥❣ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ t❡❝❤♥✐q✉❡ ❛♥❞ ❝♦♠♣❛r❡

t❤❡ r❡s✉❧ts ✇✐t❤ t❤♦s❡ ♠❡❛s✉r❡❞ ♦♥ t❤❡ ■❇▼ ♣❛tt❡r♥s✳ ❚❤❡ st❛t❡ ✈❛r✐❛❜❧❡ ♦❢ t❤❡

♠♦♠❡♥t ♠♦❞❡❧ ❛r❡ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s N ✭t❤❡ ✜rst s♣❛t✐❛❧ ♠♦♠❡♥t✮

❛♥❞ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ C(ξ) ✭t❤❡ s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥t✮ ✇❤❡r❡ ξ =

(ξ1, ξ2) ✐s ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡✳ ❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡s❡ ✈❛r✐❛❜❧❡s ✐s ❣✐✈❡♥ ❜②✿

dN

dt= b1N − d1N − d′1

K

(

||ξ||

wd

)

C(ξ)dξ ✭✹✳✺✮

❚❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ t❡r♠s ♦♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ✭❘❍❙✮ ❛r❡ r❡❧❛t✐✈❡ t♦ t❤❡

♥❡✐❣❤❜♦r❤♦♦❞✲✐♥❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss❡s✳ ❚❤❡ t❤✐r❞ t❡r♠ ✐♥

t❤❡ ❘❍❙ ✐s t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞✲❞❡♣❡♥❞❡♥t ❝♦♠♣♦♥❡♥t ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss✳ ❚❤❡

✐♥t❡❣r❛❧ t❡r♠ ✐♥✈♦❧✈❡s t❤❡ ♣❛✐r ❞❡♥s✐t② ❢✉♥❝t✐♦♥ C(ξ) ❛♥❞ t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧

K(||ξ||/wd)✳ ❚❤✐s t❡r♠ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❡✛❡❝t ♦❢ t❤❡ ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ♦♥ t❤❡ ♠❡❛♥

❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✇❤✐❝❤ ✐s t❤❡ r❡s✉❧t ♦❢ t❤❡ s♣❛t✐❛❧ str✉❝t✉r❡✱ ❛s ❣✐✈❡♥ ❜② C(ξ)✱

❛♥❞ ♦♥ t❤❡ ❡①t❡♥t t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❡①♣❡r✐❡♥❝❡ t❤❡ ❡✛❡❝t ♦❢ t❤✐s str✉❝t✉r❡ ❛s ❣✐✈❡♥ ❜②

K(||ξ||/wd)✳ ◆♦t❡ t❤❛t ✐❢ t❤❡ s✐❞❡ ♦❢ t❤❡ ✉♥✐❢♦r♠ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧✱ wd✱ ✐s ❡q✉❛❧

t♦ t❤❡ s✐❞❡ L ♦❢ t❤❡ ❞♦♠❛✐♥ t❤❛♥ ❡q✉❛t✐♦♥ ✹✳✺ ❝❛♥ ❜❡ s✐♠♣❧✐✜❡❞ t♦ t❤❡ ♠❡❛♥✲✜❡❧❞

❡q✉❛t✐♦♥✿

dN

dt= (b1 − d1)N − d′1N

2 ✭✹✳✻✮

❲❡ s✉♣♣♦s❡ ❤♦✇❡✈❡r t❤❛t t❤❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ ✐s r❡❧❛t✐✈❡❧② s♠❛❧❧ ✭wd = 3

t♦ 31✮ ❝♦♠♣❛r❡❞ t♦ t❤❡ s✐③❡ ♦❢ t❤❡ ❞♦♠❛✐♥ ✭L = 201✮✳ ❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ♣❛✐r

❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✐s ❣✐✈❡♥ ❜②✿

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✺✽

❈❤❛♣t❡r ✹✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤

❞❡t❛❝❤♠❡♥t

✭❛✮ wd = 3

✭❜✮ wd = 19

❋✐❣✉r❡ ✹✳✷✿ ✭◗✉❛s✐✮ st❛t✐♦♥❛r② s♣❛t✐❛❧ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❢♦r wb = 19 ❛♥❞

✈❛r✐❛❜❧❡ wd

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✹✳✹✳ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✺✾

✭❛✮ wd = 3

✭❜✮ wd = 19

❋✐❣✉r❡ ✹✳✸✿ ✭◗✉❛s✐✮ st❛t✐♦♥❛r② s♣❛t✐❛❧ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❢♦r wb = 3 ❛♥❞

✈❛r✐❛❜❧❡

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✻✵

❈❤❛♣t❡r ✹✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤

❞❡t❛❝❤♠❡♥t

✭❛✮ wd = 19 ✭❜✮ wd = 31

❋✐❣✉r❡ ✹✳✹✿ ✭◗✉❛s✐✮ st❛t✐♦♥❛r② s♣❛t✐❛❧ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❢♦r wb = 3 ❛♥❞

❧❛r❣❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧s

dC(ξ)

dt= 2b1NK

(

||ξ||

wb

)

+ 2b1

K

(

||ξ′||

wb

)

C(ξ + ξ′)dξ′ ✭✹✳✼✮

− 2d1C(ξ)− 2d′1K

(

||ξ||

wd

)

C(ξ)− d′1

K

(

||ξ′′||

wd

)

T (ξ, ξ′′)dξ′′ −

− d′1

K

(

||ξ′′||

wd

)

T (−ξ, ξ′′)dξ′′

❚❤❡ ✜rst ❛♥❞ s❡❝♦♥❞ t❡r♠s ♦♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ❛❝❝♦✉♥t ❢♦r t❤❡ ❢♦r♠❛t✐♦♥ ♦❢

♥❡✇ ♣❛✐rs ❛t ❞✐st❛♥❝❡ ξ t❤r♦✉❣❤ ❞✐✈✐s✐♦♥ ❡✈❡♥ts ❛♥❞ ❛r❡ ❡①♣❧❛✐♥❡❞ ✐♥ t❤❡ ♣r❡✈✐♦✉s

❝❤❛♣t❡r✳ ❚❤❡ t❤✐r❞ t♦ s✐①t❤ t❡r♠s ❛❝❝♦✉♥t ❢♦r t❤❡ ❡✛❡❝t ♦❢ ❞❡t❛❝❤♠❡♥t✳ ❚❤❡s❡

❧❛st t❤r❡❡ t❡r♠s ❛r❡ ♥❡❣❛t✐✈❡ ❛s ❞❡t❛❝❤♠❡♥t ❡❧✐♠✐♥❛t❡s ♣❛✐rs✳ ❋♦❧❧♦✇✐♥❣ ✐s ❛ ♠♦r❡

❞❡t❛✐❧❡❞ ❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡s❡ s✐① t❡r♠s✿

• t❤❡ ✜rst t❡r♠ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧

i ♣r♦❞✉❝✐♥❣ ❛ ♥❡✇ ✐♥❞✐✈✐❞✉❛❧ j ❧♦❝❛t❡❞ ❛t ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ✳ ▼✉❧t✐♣❧②✐♥❣

t❤❡ ♠❡❛♥ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s N ❜② t❤❡ ✐♥❞❡♣❡♥❞❡♥t ♣❡r ❝❛♣✐t❛ ❞✐✈✐s✐♦♥ r❛t❡

b1 ❣✐✈❡s t❤❡ r❛t❡ ♦❢ ❞✐✈✐s✐♦♥ ❡✈❡♥ts✳ ❚❤❡♥ ✇❡ ♠✉❧t✐♣❧② ❜② t❤❡ ♣r♦❜❛❜✐❧✐t② t❤❛t

t❤❡ ♥❡✇❧② ❢♦r♠❡❞ ❝❡❧❧ ✐s ❧♦❝❛t❡❞ ❛t ❞✐st❛♥❝❡ ξ ❢r♦♠ t❤❡ ♣❛r❡♥t ♣♦s✐t✐♦♥✳ ❚❤❡

❢❛❝t♦r ✷ ❛❝❝♦✉♥ts ❢♦r ♥❡✇❧② ❢♦r♠❡❞ ✐♥❞✐✈✐❞✉❛❧s t❤❛t ❞✐s♣❡rs❡ t♦ ❞✐st❛♥❝❡ −ξ

✇❤✐❝❤ ❛❧s♦ ❢♦r♠ ❛ ♥❡✇ ♣❛✐r (j, i) ❛t ❞✐st❛♥❝❡ ξ✳

• t❤❡ s❡❝♦♥❞ t❡r♠ ❛❧s♦ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥✱ ❜✉t ❢♦❝✉s❡s

♦♥ t❤❡ ♥❡✇ ♣❛✐r t❤❛t t❤❡ ♦✛s♣r✐♥❣ ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧ i ❢♦r♠s ✇✐t❤ ❛♥❞ ✐♥❞✐✈✐❞✉❛❧

j ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ+ξ′ ❢r♦♠ i✳ ❚❤❡ ♣❡r ❝❛♣✐t❛ r❛t❡ ♦❢ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t

❞✐✈✐s✐♦♥ ✐s b1✱ t❤❡ ❞❡♥s✐t② ♦❢ (i, j) ♣❛✐rs ✐s C(ξ + ξ′) ❛♥❞ t❤❡ s♣❛t✐❛❧ ❞❡♥s✐t② ♦❢

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✹✳✺✳ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ t❤❡ ■❇▼ ✻✶

♦✛s♣r✐♥❣ s❡tt❧✐♥❣ ❛r♦✉♥❞ t❤❡ i ♣❛r❡♥t ✐s K(||ξ′||/wb)✳ ▼✉❧t✐♣❧②✐♥❣ t❤❡s❡ t❤r❡❡

❢❛❝t♦rs ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ♣♦ss✐❜❧❡ ❞✐st❛♥❝❡s ξ′ ♦❢ ♦✛s♣r✐♥❣ ❞✐s♣❡rs❛❧ ②✐❡❧❞s

t❤❡ s❡❝♦♥❞ t❡r♠✳

• t❤❡ t❤✐r❞ t❡r♠ ❛❝❝♦✉♥ts ❢♦r ij ♣❛✐rs t❤❛t ❛r❡ ❧♦st ❞✉❡ t♦ t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t

❞❡❛t❤ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ✐♥ t❤❡ ♣❛✐r ✭r❡s♣❡❝t✐✈❡❧② j✮✳

• t❤❡ ❢♦✉rt❤ t❡r♠ ❝♦rr❡❝ts t❤❡ ❞❡❛t❤ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ✐♥ t❤❡ ♣❛✐r ij ❜②

❛❞❞✐♥❣ t❤❡ ❡✛❡❝t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ j ♦♥ t❤❡ ❞❡❛t❤ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i✳

• t❤❡ ✜❢t❤ ❛♥❞ s✐①t❤ t❡r♠s ❝♦rr❡❝t t❤❡ ❞❡❛t❤ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ✐♥ t❤❡ ♣❛✐r ij

❜② ❛❞❞✐♥❣ t❤❡ ❡✛❡❝t ♦❢ ♥❡✐❣❤❜♦rs ✭♦t❤❡r t❤❛♥ j✮ ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ′′ ❢r♦♠ i✳

❚❤❡ ❞❡♥s✐t② ♦❢ t❤✐s tr✐♣❧❡t ❝♦♥✜❣✉r❛t✐♦♥ ✐s ❣✐✈❡♥ ❜② t❤❡ tr✐♣❧❡ ❞❡♥s✐t② ❢✉♥❝t✐♦♥

T (ξ, ξ′′) ❛♥❞ T (−ξ, ξ′′) ❲❡ ♠✉❧t✐♣❧② ❜② t❤❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ ❝❛❧❝✉❧❛t❡❞ ❛t

❞✐st❛♥❝❡ ξ′′ ❛♥❞ ✐♥t❡❣r❛t❡ ♦✈❡r ❛❧❧ ♣♦ss✐❜❧❡ ♥❡✐❣❤❜♦rs ✭♦r ❛❧❧ ❞✐st❛♥❝❡s ξ′′✮✳

❚❤❡ s②st❡♠ ❢♦r♠❡❞ ✇✐t❤ ❡q✉❛t✐♦♥s ✹✳✺ ❛♥❞ ✹✳✼ ✐♥✈♦❧✈❡s t❤❡ t❤✐r❞ s♣❛t✐❛❧ ♠♦♠❡♥t

T (ξ, ξ′)✳ ❚♦ ❝❧♦s❡ t❤✐s s②st❡♠ ✇❡ ♥❡❡❞ t♦ ❡①♣r❡ss t❤❡ t❤✐r❞ ♠♦♠❡♥t ❛s ❛ ❢✉♥❝t✐♦♥

♦❢ t❤❡ ✜rst ❛♥❞ t❤❡ s❡❝♦♥❞ ♠♦♠❡♥ts✳ ❲❡ ✉s❡ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❧♦s✉r❡ ❡①♣r❡ss✐♦♥s

❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪✿

T (ξ, ξ′) =C(ξ)C(ξ′)C(ξ′ − ξ)

N3✭✹✳✽✮

❆s ✇✐❧❧ ❜❡ ❞❡t❛✐❧❡❞ ✐♥ t❤❡ ♥❡①t ♣❛r❛❣r❛♣❤ t❤❡ ❝❤♦✐❝❡ ♦❢ t❤❡ ❝❧♦s✉r❡ ❡①♣r❡ss✐♦♥

❝❛♥ ❤❛✈❡ ❛ s✐❣♥✐✜❝❛♥t ✐♠♣❛❝t ♦♥ t❤❡ s✐♠✉❧❛t❡❞ ♣❛tt❡r♥✳ ❚❤✐s ❝❤♦✐❝❡ ✐s ❣✉✐❞❡❞ ❜②

t❤❡ ❝♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ❛♥❞ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♣❛tt❡r♥s✳ ❆ ❣♦♦❞

❝❧♦s✉r❡ ✐s t❤❡ ♦♥❡ t❤❛t ❛❧❧♦✇s t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ t♦ ❝❛♣t✉r❡ t❤❡ ♠❛✐♥ ❢❡❛t✉r❡s ♦❢ t❤❡

♣❛tt❡r♥s ❛♥❞ ❞②♥❛♠✐❝s ②✐❡❧❞❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✳

❲❡ s♦❧✈❡ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❢♦r♠❡❞ ✇✐t❤ ❡q✉❛t✐♦♥s ✹✳✺✱ ✹✳✼✱ ✹✳✽ ❛♥❞ ❄❄✱ ❛s

❞❡t❛✐❧❡❞ ✐♥ t❤❡ ♣r❡✈✐♦✉s ❝❤❛♣t❡r✱ ❜② ❞✐s❝r❡t✐③✐♥❣ t❤❡ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡s ξ ✇✐t❤ ❛

s♣❛t✐❛❧ r❡s♦❧✉t✐♦♥ dξ = (dξ1, dξ2) ❛♥❞ t✐♠❡ ✇✐t❤ ❛ ❝♦♥st❛♥t t✐♠❡ st❡♣ ∆t✳ ❲❡ ✉s❡ ❛♥

❡①♣❧✐❝✐t ❊✉❧❡r s❝❤❡♠❡ ❢♦r ❞❡s❝r✐t✐③✐♥❣ t❤❡ t✐♠❡ ❞❡r✐✈❛t✐✈❡✳ ❚❤❡ r❡s✉❧t❛♥t ❛❧❣❡❜r❛✐❝

s②st❡♠ ✐s ❢♦r♠❡❞ ✇✐t❤ n2x + 1 ❡q✉❛t✐♦♥ ✭✇❤❡r❡ nx ✐s t❤❡ s✐③❡ ♦❢ ❞✐s❝r❡t✐③❡❞ C(ξ)

❡①♣r❡ss❡s t❤❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s N ❛♥❞ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ♠❛tr✐① C(ξ) ❛t t❤❡

✐♥st❛♥t t+∆t ❛s ❛ ❢✉♥❝t✐♦♥ ♦❢ N ❛♥❞ C ❛t t❤❡ ♣r❡✈✐♦✉s ✐♥st❛♥t t✳

✹✳✺ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ t❤❡ ■❇▼

❲❡ ❝♦♠♣❛r❡ t❤❡ t✐♠❡ ❝♦✉rs❡ ♦❢ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ②✐❡❧❞❡❞ ❜② t❤❡

■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✭✜❣✉r❡ ✹✳✺✮ ❛♥❞ t❤❡ st❛t✐♦♥❛r② r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥

❢✉♥❝t✐♦♥ ✭✜❣✉r❡ ✹✳✻✮✳ ❋♦r ❛ ❧❛r❣❡ ❜✐rt❤ ❦❡r♥❡❧ wb = 19✱ t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t

♠♦❞❡❧s ②✐❡❧❞s ❝♦♠♣❛r❛❜❧❡ r❡s✉❧ts t♦ t❤♦s❡ ♦❜t❛✐♥❡❞ ✇✐t❤ t❤❡ ♠❡❛♥✲✜❡❧❞ ❧✐♠✐t ✭❞❛s❤❡❞

❧✐♥❡ ✐♥ ✜❣✉r❡ ✹✳✺✭❛✮✮✳ ■♥ t❤✐s ❝❛s❡ ✇❤❡r❡ t❤❡ ❞✐str✐❜✉t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐s ✉♥✐❢♦r♠

❛s ❝❛♥ ❜❡ s❡❡♥ ❢r♦♠ t❤❡ ♣❛✐r ❞❡♥s✐t② ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s ✐♥ ✜❣✉r❡ ✹✳✻✭❛✮✇❤✐❝❤ t❛❦❡

✈❛❧✉❡s ❝❧♦s❡ t♦ ✶ ✐♥ ❜♦t❤ ♠♦❞❡❧s ✐♥❞✐❝❛t✐♥❣ t❤❛t t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣❛✐rs ✐s ❛❧♠♦st

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✻✷

❈❤❛♣t❡r ✹✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤

❞❡t❛❝❤♠❡♥t

❡q✉❛❧ t♦ N2 ✭t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs ✐♥ t❤❡ s②st❡♠✮ ❋♦r s♠❛❧❧ ❜✐rt❤ ❦❡r♥❡❧s

❤♦✇❡✈❡r✱ t❤❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐♥❝r❡❛s❡s ✐♥ ❜♦t❤ ♠♦❞❡❧s ❜❡②♦♥❞ t❤❡ st❛t✐♦♥❛r②

✈❛❧✉❡ ②✐❡❧❞❡❞ ❜② t❤❡ ♠❡❛♥✲✜❡❧❞ ♠♦❞❡❧✳ ❚❤✐s ✐s ❛ ❝♦✉♥t❡r ✐♥t✉✐t✐✈❡ r❡s✉❧t ❛s ♦♥❡ ♠❛②

❡①♣❡❝t t❤❛t t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❛❣❣r❡❣❛t❡s ✇♦✉❧❞ ✐♥❝r❡❛s❡ t❤❡ ❞❡t❛❝❤♠❡♥t r❛t❡ ♦❢ t❤❡

✐♥❞✐✈✐❞✉❛❧s ②✐❡❧❞✐♥❣ ❧♦✇❡r ❡q✉✐❧✐❜r✐✉♠ ❞❡♥s✐t② t❤❛♥ ✇❤❛t ✇♦✉❧❞ ❜❡ ♦❜t❛✐♥❡❞ ✐♥ t❤❡

❝❛s❡ ♦❢ ❛ ✉♥✐❢♦r♠ ❞✐str✐❜✉t✐♦♥✳ ❚❤❡ ♦r❣❛♥✐③❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✇✐t❤ ❛ r❡❣✉❧❛r

❞✐st❛♥❝❡ ✐s ❧✐❦❡❧② t♦ ✐♥❞✉❝❡ ❛ ❧♦✇❡r ❛✈❡r❛❣❡ ❞❡t❛❝❤♠❡♥t r❛t❡ ❛s t❤✐s ❛rr❛♥❣❡♠❡♥t

s❡❡♠s t♦ ♠✐♥✐♠✐③❡ t❤❡ ❝♦♠♣❡t✐t✐♦♥ ✇✐t❤ r❡❣❛r❞ t♦ ❞❡t❛❝❤♠❡♥t ❜❡t✇❡❡♥ t❤❡ ❝♦❧♦♥✐❡s✳

❚❤❡ ♣❛tt❡r♥ ♦❢ ✐s♦❧❛t❡❞ ❝♦❧♦♥✐❡s ②✐❡❧❞s ❛♥ ♦s❝✐❧❧❛t✐♥❣ r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝✲

t✐♦♥✳ ❚❤❡ ✜rst ♣❡❛❦ ✐s ❞✉❡ t♦ t❤❡ ❤✐❣❤ ❞❡♥s✐t② ♦❢ ♥❡✐❣❤❜♦rs ✇✐t❤✐♥ t❤❡ ❝♦❧♦♥② ✭s❤♦rt

❞✐st❛♥❝❡✮✳ t❤❡ ✇❛✈❡s ❛r❡ ❞✉❡ t♦ t❤❡ r❡❣✉❧❛r ❛rr❛♥❣❡♠❡♥t ♦❢ t❤❡ ❝♦❧♦♥✐❡s✳ ❚❤❡ ♣❡❛❦s

✐♥ t❤❡ ■❇▼ ❛r❡ ❧♦✇❡r t❤❛♥ t❤♦s❡ ②✐❡❧❞❡❞ ❜② t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ t❤❡ ✇❛✈② r❛❞✐❛❧

♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ s❡❡♠s t♦ ✈❛♥✐s❤ t♦ ✶ ✐♥ t❤❡ ■❇▼ ❢♦r ❧❛r❣❡ ❞✐st❛♥❝❡s✳ ❚❤✐s

✐s ❞✉❡ t♦ t❤❡ ✢✉❝t✉❛t✐♦♥s ❛r♦✉♥❞ t❤❡ ❝♦❧♦♥✐❡s s✐♠✉❧❛t❡❞ ❜② t❤❡ ■❇▼✳ ❚❤❡ ✐♥❞✐✈✐❞✉✲

❛❧s ❛r❡ ✐♥ ♠❛❥♦r✐t② ❡♥❝❧♦s❡❞ ✇✐t❤✐♥ t❤❡ ❝♦❧♦♥✐❡s ❜✉t s♦♠❡ ♦❢ t❤❡♠ ❛r❡ st✐❧❧ ❜❡t✇❡❡♥

t❤❡ ❝♦❧♦♥✐❡s ❞✉❡ t♦ t❤❡ st♦❝❤❛st✐❝ ❞✐✈✐s✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss✳ ❚❤✐s ❜❧✉rs t❤❡

❞❡t❡r♠✐♥✐st✐❝ ❡❝♦❧♦❣✐❝❛❧ s✐❣♥❛❧ ❛s r❡✈❡❛❧❡❞ ❜② t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳

✹✳✻ ❉✐s❝✉ss✐♦♥

❲❡ ❛♣♣r♦①✐♠❛t❡❞ t❤❡ ❞②♥❛♠✐❝ ♦❢ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ✇✐t❤ ❛ ♣♦♣✉❧❛t✐♦♥ ♦❢ ✐♥❞✐✈✐❞✉❛❧s

✐♥❤❛❜✐t✐♥❣ ❛ t✇♦✲❞✐♠❡♥s✐♦♥❛❧ ❞♦♠❛✐♥✳ ❚❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛r❡ s✉❜❥❡❝t t♦ ❞✐✈✐s✐♦♥ ❡✈❡♥ts

❛♥❞ ❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss✳ ❚❤❡ ♥✉♠❡r✐❝❛❧ ❡①♣❧♦r❛t✐♦♥ ♦❢ t❤❡

■❇▼ s❤♦✇s ❢♦r ❧❛r❣❡ ❜✐rt❤ ❦❡r♥❡❧s t❤❡ ♥❡✇❜♦r♥ ❝❡❧❧s ❞✐s♣❡rs❡ ♦✈❡r ❧❛r❣❡ ❞✐st❛♥❝❡s

♣r❡✈❡♥t✐♥❣ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s✳ ■♥ t❤✐s ❝❛s❡ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ②✐❡❧❞❡❞ ❜② t❤❡

■❇▼ ❡✈♦❧✈❡ ❛s ✐♥ t❤❡ ♠❡❛♥✲✜❡❧❞ ❧✐♠✐ts✳

❍♦✇❡✈❡r ✇❤❡♥ ✇❡ r❡❞✉❝❡ t❤❡ s✐③❡ ♦❢ t❤❡ ❜✐rt❤ ❦❡r♥❡❧✱ ♣❛tt❡r♥s ✇✐t❤ ✐s♦❧❛t❡❞

♠✐❝r♦❝♦❧♦♥✐❡s ♠❛② ❡♠❡r❣❡ ❛♥❞ ❝❛♥ ❜❡ ♦❜s❡r✈❡❞ ❡s♣❡❝✐❛❧❧② ✇❤❡♥ t❤❡ s✐③❡ ♦❢ t❤❡ ❞❡✲

t❛❝❤♠❡♥t ❦❡r♥❡❧ ✐s ❤✐❣❤❡r t❤❛♥ t❤❛t ♦❢ t❤❡ ❜✐rt❤ ❦❡r♥❡❧✳

❲❡ ❛♣♣r♦①✐♠❛t❡❞ t❤❡ ■❇▼ ✇✐t❤ ❛ ♠♦♠❡♥t ♠♦❞❡❧✳ ▼♦♠❡♥t ♠♦❞❡❧ ❛tt❡♠♣ts t♦

❝❛♣t✉r❡ ❤♦✇ t❤❡ ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❡✈♦❧✈❡ ✐♥ t✐♠❡ ❛♥❞ ❤♦✇ ✐t ❛✛❡❝ts

t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡ ❞❡r✐✈❡❞ ♠♦♠❡♥t ♠♦❞❡❧ ✐s ❣❧♦❜❛❧❧② ✐♥ ❛ ❣♦♦❞

❛❣r❡❡♠❡♥t ✇✐t❤ t❤❡ ■❇▼✳ ▼♦♠❡♥t ♠♦❞❡❧ ♣r❡❞✐❝ts ❛ P♦✐ss♦♥✲❧✐❦❡ ❞✐str✐❜✉t✐♦♥ ✐♥ t❤❡

❝❛s❡ ♦❢ ❧❛r❣❡ ❜✐rt❤ ❦❡r♥❡❧s ❛♥❞ ❛♥ ♦s❝✐❧❧❛t✐♥❣ r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✱ ✐♥ t❤❡

❝❛s❡ ♦❢ s♠❛❧❧ ❞✐s♣❡rs✐♦♥ ❛♥❞ ❧❛r❣❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧✱ ✇✐t❤ ❛ ♣❡r✐♦❞ ❛♣♣r♦①✐♠❛t✐✈❡❧②

❝♦rr❡s♣♦♥❞✐♥❣ t♦ t❤❡ s✐③❡ ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧✳ ❚❤❡ ♣❡❛❦s ✐♥ t❤❡ ♦s❝✐❧❧❛t✐♥❣

♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ❤♦✇❡✈❡r ❛r❡ ❤✐❣❤ ✐♥ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ t❤❛♥ ✐♥ t❤❡ ■❇▼✳

❚❤✐s ♠❛② ❜❡ ❡①♣❧❛✐♥❡❞ ❜② t❤❡ ❝❤♦✐❝❡ ♦❢ t❤❡ ❝❧♦s✉r❡✳ ❚❤❡ ❝❧♦s✉r❡ ❡①♣r❡ss❡s t❤❡ t❤❡

t❤✐r❞ ♠♦♠❡♥t ✐♥ t❡r♠ ♦❢ ✜rst ❛♥❞ s❡❝♦♥❞ ♠♦♠❡♥ts✳ ❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ r❡s✉❧ts ❝❛♥

❜❡ ✈❡r② s❡♥s✐t✐✈❡ t♦ t❤❡ ❝❤♦✐❝❡ ♦❢ t❤❡ ❝❧♦s✉r❡ ❡①♣r❡ss✐♦♥✳ ❋♦r ✐♥st❛♥❝❡ t❤❡ ❝❧❛ss✐❝❛❧

s❡❝♦♥❞ ♦r❞❡r ❝❧♦s✉r❡s ✭T (ξ, ξ′) = C(ξ′)C(ξ)/N✮ ❢❛✐❧s ✐♥ ♣r❡❞✐❝t✐♥❣ t❤❡ ✇❛✈② str❝t✉r❡

♦❢ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ✇❤✐❧❡ t❤❡ t❤✐r❞ ♦r❞❡r ❝❧♦s✉r❡ ♦✈❡r❡st✐♠❛t❡s t❤❡ ❤✐❣❤t ♦❢ t❤❡

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✹✳✻✳ ❉✐s❝✉ss✐♦♥ ✻✸

✭❛✮ wb = 19, wd = 19

✭❜✮ wb = 3, wd = 19

❋✐❣✉r❡ ✹✳✺✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t✐❡s ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✭✜rst s♣❛t✐❛❧ ♠♦♠❡♥t✮

❝❛❧❝✉❧❛t❡❞ ✇✐t❤ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ s✐♠✉❧❛t❡❞ ✇✐t❤ t❤❡ ■❇▼ ❢♦r ❞✐✛❡r❡♥t ❜✐rt❤

❦❡r♥❡❧ s✐③❡s✿ wb = 19 ❛♥❞ 3 ✭❉♦♠❛✐♥ s✐③❡ 201× 201 ❛♥❞ wd = 19✮

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✻✹

❈❤❛♣t❡r ✹✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛ s✐♠♣❧✐✜❡❞ ❜✐♦✜❧♠ ■❇▼ ✇✐t❤

❞❡t❛❝❤♠❡♥t

✭❛✮ wb = 19

✭❜✮ wb = 3

❋✐❣✉r❡ ✹✳✻✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ r❛❞✐❛❧ ♣❛✐r ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t

♠♦❞❡❧ ❢♦r wd = 19 ❛♥❞ ❞✐✛❡r❡♥t s✐③❡s ♦❢ t❤❡ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧

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✹✳✻✳ ❉✐s❝✉ss✐♦♥ ✻✺

♣❡❛❦s✳

❚❤✐s ✐s ♦♥❡ ♦❢ t❤❡ ❧✐♠t❛t✐♦♥s ♦❢ ♠♦♠❡♥t ♠♦❞❡❧s ✇❤✐❝❤ ♣r♦✈✐❞❡ ❞❡t❡r♠✐♥✐st✐❝ ❛♣✲

♣r♦①✐♠❛t✐♦♥s ♦❢ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✳ ❚❤❡ q✉❛❧✐t② ♦❢ t❤❡ ❛♣✲

♣r♦①✐♠❛t✐♦♥ ♥❡❡❞ t♦ ❜❡ ❛ss❡ss❡❞ t❤r♦✉❣❤ ❝♦♠♣❛r✐s♦♥ t♦ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

s✐♠✉❧❛t✐♦♥s ❛♥❞ ✐♠♣r♦✈❡❞ ❜② s❡❧❡❝t✐♥❣ t❤❡ ❜❡st ❝❧♦s✉r❡ ❡①♣r❡ss✐♦♥✳

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❈❤❛♣t❡r ✺

❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡

❜❛❝t❡r✐❛

P✉❜❧✐s❤❡❞ ✐♥ ❚❤❡♦r② ✐♥ ❇✐♦s❝✐❡♥❝❡s✿ ▼❛❜r♦✉❦✱ ◆✳✱ ❉❡✛✉❛♥t✱●✳✱❚♦❧❦❡r✲◆✐❡❧s❡♥✱❚✳✱

▲♦❜r②✱❈✳✿ ❇❛❝t❡r✐❛ ❝❛♥ ❢♦r♠ ✐♥t❡r❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ✇❤❡♥ ❛ s❡❧❢✲❡①❝r❡t❡❞ ♣r♦❞✲

✉❝t r❡❞✉❝❡s t❤❡✐r s✉r❢❛❝❡ ♠♦t✐❧✐t②✿ ❡✈✐❞❡♥❝❡ ❢r♦♠ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ s✐♠✉❧❛t✐♦♥✳

❉❖■✿ ✶✵✳✶✵✵✼✴s✶✷✵✻✹✲✵✵✾✲✵✵✼✽✲✽

❈♦♥t❡♥ts

✺✳✶ ❇❛❝❦❣r♦✉♥❞ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✽

✺✳✷ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✻✾

✺✳✷✳✶ P✉r♣♦s❡ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵

✺✳✷✳✷ ❙t❛t❡ ✈❛r✐❛❜❧❡s ❛♥❞ s❝❛❧❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵

✺✳✷✳✸ ❙❝❛❧❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵

✺✳✷✳✹ Pr♦❝❡ss ♦✈❡r✈✐❡✇ ❛♥❞ s❝❤❡❞✉❧✐♥❣ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✵

✺✳✷✳✺ ❉❡s✐❣♥ ❈♦♥❝❡♣ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✷

✺✳✷✳✻ ❙✉❜♠♦❞❡❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✷

✺✳✸ ❘❡s✉❧ts ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✼

✺✳✹ ❉✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✼✾

❲❡ ♣r♦♣♦s❡ t♦ ❛♥❛❧②③❡ ✉s✐♥❣ ♥✉♠❡r✐❝❛❧ ❡①♣❡r✐♠❡♥t❛t✐♦♥s ❛ ♥❡✇ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧ ♦❢ ❛ ♠✐❝r♦❜✐❛❧ s②st❡♠ ❢♦r♠❡❞ ✇✐t❤ s✉r❢❛❝❡✲❛ss♦❝✐❛t❡❞ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✇❤✐❝❤

♠♦t✐❧✐t② ✐s r❡❞✉❝❡❞ ❜② ❛ s❡❧❢✲❡①❝r❡t❡❞ s✉❜st❛♥❝❡✳ ❚❤❡ ♠♦❞❡❧ ✐s ✐♥s♣✐r❡❞ ❢r♦♠ r❡✲

❝❡♥t ❡①♣❡r✐♠❡♥t❛❧ ♦❜s❡r✈❛t✐♦♥s ♦❢ Ps❡✉❞♦♠♦♥❛s ❛❡r✉❣✐♥♦s❛✱ ❛ ♠♦❞❡❧ ❜❛❝t❡r✐✉♠ ✐♥

❜✐♦✜❧♠ r❡s❡❛r❝❤ t❤❛t ❤❛✈❡ ❜❡❡♥ s❤♦✇♥ t♦ ❜✐♥❞✱ ✉♥❞❡r s♣❡❝✐✜❝ ❣r♦✇t❤ ❝♦♥❞✐t✐♦♥s✱ t♦

s❡❧❢✲❡①❝r❡t❡❞ ❉◆❆✳ ❚❤❡s❡ ❡①♣❡r✐♠❡♥t❛❧ ♦❜s❡r✈❛t✐♦♥s ❛❧s♦ s❤♦✇❡❞ t❤❛t Ps❡✉❞♦♠♦♥❛s

❛❡r✉❣✐♥♦s❛ ❢♦r♠s ✐♥t❡r❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ❛♥❞ ♣r❡s✉♠❡❞ ❛ ♣♦ss✐❜❧❡ ✐♥✈♦❧✈❡♠❡♥t

♦❢ t❤❡ ❡①tr❛❝❡❧❧✉❧❛r ❉◆❆ ✐♥ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡s❡ ♣❛tt❡r♥s✳ ■♥ t❤✐s ❝❤❛♣t❡r✱ ✇❡ ✉s❡

❛♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ t♦ ❛ss❡ss t❤❡ ✐♥✈♦❧✈❡♠❡♥t ♦❢ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② ❛♥❞ ✐♥t❡r✲

❛❝t✐♦♥ ✇✐t❤ s❡❧❢✲❡①❝r❡t❡❞ ❡①tr❛❝❡❧❧✉❧❛r s✉❜st❛♥❝❡ ✐♥ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ♣❛tt❡r♥s ✇✐t❤

✐♥t❡r❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s✳ ❖✉r ❛♥❛❧②s✐s ✐s ❜❛s❡❞ ♦♥ ♥✉♠❡r✐❝❛❧ ❡①♣❡r✐♠❡♥t❛t✐♦♥s

✉s✐♥❣ t❤❡ ■❇▼ ❛♥❞ st❛rt✐♥❣ ✇✐t❤ ♦❜✈✐♦✉s ❝❛s❡s t❤❛♥ ♠♦✈✐♥❣ ♣r♦❣r❡ss✐✈❡❧② t♦ t❤❡

❝❛s❡ ♦❢ ✐♥t❡r❡st✳

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✻✽

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

✺✳✶ ❇❛❝❦❣r♦✉♥❞

▼❛♥② ❜❛❝t❡r✐❛ ❤❛✈❡ ❛♥ ✐♥♥❛t❡ ♣r♦♣❡♥s✐t② t♦ ❢♦r♠ ❜✐♦✜❧♠s✿ t❤❡② ❜✉✐❧❞ str✉❝✲

t✉r❡❞ ♠✉❧t✐❝❡❧❧✉❧❛r ❝♦♠♠✉♥✐t✐❡s ❛tt❛❝❤❡❞ t♦ s♦❧✐❞ s✉r❢❛❝❡s✳ ▼✐❝r♦s❝♦♣✐❝ ❡①❛♠✐♥❛✲

t✐♦♥ ♦❢ ❜✐♦✜❧♠s ❢♦r♠❡❞ ❜② Ps❡✉❞♦♠♦♥❛s ❛❡r✉❣✐♥♦s❛✱ ❛ ♠♦❞❡❧ ❜❛❝t❡r✐✉♠ ✐♥ ❜✐♦✜❧♠

r❡s❡❛r❝❤ ❬❈♦st❡rt♦♥ ✶✾✾✺❪❬❉❛✈❡② ✷✵✵✵❪✱ r❡✈❡❛❧s ❛ ✇✐❞❡ ❞✐✈❡rs✐t② ♦❢ s♣❛t✐❛❧ ♣❛tt❡r♥s

✇❤✐❝❤✱ ❞❡♣❡♥❞✐♥❣ ♦♥ t❤❡ ❣r♦✇t❤ ❝♦♥❞✐t✐♦♥s✱ r❛♥❣❡ ❢r♦♠ ❛ ✢❛t t❤✐♥ ❧❛②❡r ♦❢ ❝❡❧❧s

t♦ ❛ ♣❛t❝❤② ♣❛tt❡r♥ ✇✐t❤ ✐♥t❡r❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ❤❛✈✐♥❣ ❝♦♠♣❧❡① t♦✇❡r ♦r

♠✉s❤r♦♦♠ ❧✐❦❡ s❤❛♣❡s ❬❑❧❛✉s❡♥ ✵✵✸❜❪❬❇❛r❦❡♥ ✷✵✵✽❪✳ ❆t ❧❡❛st s♦♠❡ ❡①♣❧❛♥❛t✐♦♥ ❢♦r

t❤❡ ❞✐✛❡r❡♥t ❜✐♦✜❧♠ ♣❛tt❡r♥s ❢♦r♠❡❞ ✉♥❞❡r ❞✐✛❡r❡♥t ❝♦♥❞✐t✐♦♥s r❡❧❛t❡s t♦ s✉r❢❛❝❡

♠♦t✐❧✐t②✳ ❈♦♥❞✐t✐♦♥s t❤❛t ♣r♦♠♦t❡ ❡①t❡♥s✐✈❡ s✉r❢❛❝❡ ♠♦t✐❧✐t② ❝❛♥ ❧❡❛❞ t♦ t❤❡ ❢♦r✲

♠❛t✐♦♥ ♦❢ ✢❛t✱ ❤♦♠♦❣❡♥❡♦✉s ❜✐♦✜❧♠s✱ ✇❤❡r❡❛s ❜✐♦✜❧♠s ❝❤❛r❛❝t❡r✐③❡❞ ❜② ❛❣❣r❡❣❛t❡s

r❡s✉❧t ❢r♦♠ ❛t ❧❡❛st ❛ s✉❜♣♦♣✉❧❛t✐♦♥ ♦❢ t❤❡ ❝♦♠♠✉♥✐t② ❝❡❛s✐♥❣ t♦ ♠♦✈❡ ❛t ❛♥ ❡❛r❧②

st❛❣❡ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❛t✐♦♥ ❬P❛rs❡❦ ✷✵✵✽❪✳ ■♥ P✳ ❛❡r✉❣✐♥♦s❛ ❜✐♦✜❧♠s✱ ❢♦r♠❛t✐♦♥ ♦❢

✐♥✐t✐❛❧ ♠✐❝r♦❝♦❧♦♥✐❡s ✭st❛❧❦s✮ t❤❛t s✉❜s❡q✉❡♥t❧② ❜❡❝♦♠❡ ❝♦❧♦♥✐③❡❞ ❜② ❝❛♣✲❢♦r♠✐♥❣

❜❛❝t❡r✐❛ ✐s ♥❡❝❡ss❛r② ❢♦r t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ♠✉s❤r♦♦♠✲s❤❛♣❡❞ ♠✉❧t✐❝❡❧❧✉❧❛r str✉❝t✉r❡s

❬❑❧❛✉s❡♥ ✵✵✸❛❪❬❑❧❛✉s❡♥ ✵✵✸❜❪✳ ❚❤❡s❡ ♠✉❧t✐❝❡❧❧✉❧❛r str✉❝t✉r❡s ♦❢t❡♥ ♣r♦✈✐❞❡ ✐♠♣♦r✲

t❛♥t ❜❡♥❡✜ts s✉❝❤ ❛s ❛ ❤✐❣❤❡r t♦❧❡r❛♥❝❡ t♦ ❛❞✈❡rs❡ ❝♦♥❞✐t✐♦♥s ❬P❛rs❡❦ ✷✵✵✽❪✱ ❛♥❞ ❝❛♥

❜❡ ❝r✉❝✐❛❧ ✐♥ ✐♥❞✉str✐❛❧ ♣r♦❝❡ss❡s✳ ❚❤❡r❡❢♦r❡✱ ♠✉❝❤ ❡①♣❡r✐♠❡♥t❛❧ ❛♥❞ t❤❡♦r❡t✐❝❛❧

❡✛♦rt ✐s ❝✉rr❡♥t❧② ❞❡✈♦t❡❞ t♦ ✉♥❞❡rst❛♥❞ t❤❡✐r ♠❡❝❤❛♥✐s♠s ♦❢ ❢♦r♠❛t✐♦♥✳

❚❤❡ ❢♦r♠❛t✐♦♥ ♦❢ s♣❛t✐❛❧ ♣❛tt❡r♥s ✐♥ P✳ ❛❡r✉❣✐♥♦s❛ ❜✐♦✜❧♠s ✐♥✈♦❧✈❡s ❛ ❝♦♠✲

♣❧❡① ✐♥t❡r♣❧❛② ❜❡t✇❡❡♥ ❝❡❧❧ ♣r♦❧✐❢❡r❛t✐♦♥✱ s✉r❢❛❝❡✲❛ss♦❝✐❛t❡❞ ♠♦t✐❧✐t② ❛♥❞ t❤❡ ♣r♦✲

❞✉❝t✐♦♥ ♦❢ ❡①tr❛❝❡❧❧✉❧❛r ♠❛❝r♦♠♦❧❡❝✉❧❡s t❤❛t ❢♦r♠ ❛ str✉❝t✉r❛❧ ♠❛tr✐① ✭❢♦r ❛ r❡✲

✈✐❡✇ s❡❡ ❬P❛rs❡❦ ✷✵✵✽❪✮✳ ❊✈✐❞❡♥❝❡ ❤❛s ❜❡❡♥ ♣r♦✈✐❞❡❞ t❤❛t ❛rr❡st ♦❢ t②♣❡ ■❱

♣✐❧✐✲♠❡❞✐❛t❡❞ ♠♦t✐❧✐t② ✭t✇✐t❝❤✐♥❣ ♠♦t✐❧✐t②✮ ♣❧❛②s ❛ r♦❧❡ ✐♥ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡

✐♥✐t✐❛❧ ♠✐❝r♦❝♦❧♦♥✐❡s ✐♥ P✳ ❛❡r✉❣✐♥♦s❛ ❜✐♦✜❧♠s✱ ✇❤❡r❡❛s ✢❛❣❡❧❧❛✲ ❞r✐✈❡♥ ♠♦t✐❧✐t②

✭s✇❛r♠✐♥❣ ♠♦t✐❧✐t②✮ ♣❧❛②s ❛ r♦❧❡ ✐♥ t❤❡ s✉❜s❡q✉❡♥t ❢♦r♠❛t✐♦♥ ♦❢ t❤❡ ❝❛♣✲♣♦rt✐♦♥ ♦❢

t❤❡ ♠✉s❤r♦♦♠✲s❤❛♣❡❞ str✉❝t✉r❡s ❬❑❧❛✉s❡♥ ✵✵✸❛❪❬❑❧❛✉s❡♥ ✵✵✸❜❪❬❇❛r❦❡♥ ✷✵✵✽❪✳ ❚❤❡

❡❛r❧② st❛❣❡s ♦❢ ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t ❜② P✳ ❛❡r✉❣✐♥♦s❛ ✐s ❞❡♣❡♥❞❡♥t ♦♥ ❡①tr❛❝❡❧❧✉❧❛r

❉◆❆ ❬❲❤✐t❝❤✉r❝❤ ✷✵✵✷❪✱ ✇❤✐❝❤ ✐s ❦♥♦✇♥ t♦ ❜✐♥❞ ✇✐t❤ ❤✐❣❤ ❛✣♥✐t② t♦ t②♣❡ ■❱ ♣✐❧✐

❬❆❛s ✷✵✵✷❪❬❱❛♥ ❙❝❤❛✐❦ ✷✵✵✺❪✱ ❛ ✜♠❜r❛❡ ❡①t❡♥❞✐♥❣ ❢r♦♠ t❤❡ ❝❡❧❧ ❜♦❞② ❛♥❞ ♠❡❞✐❛t✲

✐♥❣ s✉r❢❛❝❡✲❛ss♦❝✐❛t❡❞ t✇✐t❝❤✐♥❣ ♠♦t✐❧✐t②✳ ❍❡♥❝❡ ✐t ♠❛② ❜❡ ❛ss✉♠❡❞ t❤❛t ✐♥✐t✐❛❧❧②

♠♦t✐❧❡ ❜❛❝t❡r✐❛ st♦♣ ❛♥❞ ❢♦r♠ ♠✐❝r♦❝♦❧♦♥✐❡s ✐♥ t❤❡ r❡❣✐♦♥s ♦❢ ❛❜✉♥❞❛♥t ❡①tr❛❝❡❧❧✉✲

❧❛r ❉◆❆✳ ❘❡❝❡♥t❧②✱ ❆❧❧❡s❡♥✲ ❍♦❧♠ ❡t ❛❧✳ ❬❆❧❧❡s❡♥✲❍♦❧♠ ✷✵✵✻❪ ✈✐s✉❛❧✐③❡❞ t❤❡ s♣❛t✐❛❧

❞✐str✐❜✉t✐♦♥ ♦❢ ❡①tr❛❝❡❧❧✉❧❛r ❉◆❆ ❛♥❞ ❜❛❝t❡r✐❛ ✐♥ P✳ ❛❡r✉❣✐♥♦s❛ ❜✐♦✜❧♠s✱ ❣r♦✇♥ ✐♥

✢♦✇ ❝❤❛♠❜❡rs ♦♥ ♠✐♥✐♠❛❧ ❣❧✉❝♦s❡ ♠❡❞✐✉♠✳ ■♥ ✷✲❞❛②✲♦❧❞ ❜✐♦✜❧♠s t❤❡ ❡①tr❛❝❡❧❧✉❧❛r

❉◆❆ ✇❛s ♣r❡s❡♥t ✐♥s✐❞❡ t❤❡ s♠❛❧❧ ♠✐❝r♦❝♦❧♦♥✐❡s✱ ❜✉t ❛❝❝✉♠✉❧❛t❡❞ ♠❛✐♥❧② ✐♥ t❤❡

♦✉t❡r ❧❛②❡r ♦❢ t❤❡ ♠✐❝r♦❝♦❧♦♥✐❡s ❛♥❞ ❜❡t✇❡❡♥ t❤❡ ♠✐❝r♦❝♦❧♦♥✐❡s ❢♦r♠✐♥❣ ❛ ❣r✐❞✲❧✐❦❡

str✉❝t✉r❡✳ ❩♦♦♠❡❞ ✈✐❡✇s ♦❢ t❤❡ ♠✐❝r♦❝♦❧♦♥✐❡s r❡✈❡❛❧❡❞ t❤❛t t❤❡② ✇❡r❡ ♦❢t❡♥ ✐♥t❡r✲

❝♦♥♥❡❝t❡❞ ✇✐t❤ t❤✐♥ str❛♥❞s ♦❢ ❡①tr❛❝❡❧❧✉❧❛r ❉◆❆ ❝♦✈❡r❡❞ ✇✐t❤ ❜❛❝t❡r✐❛ ✭s❡❡ ✜❣✉r❡

✺✳✶✮✳ ■♥ ✹✲❞❛②✲♦❧❞ ❜✐♦✜❧♠s ❝❛♣✲ ❧✐❦❡ ♠✉❧t✐❝❡❧❧✉❧❛r str✉❝t✉r❡s ❤❛❞ ❢♦r♠❡❞ ♦♥ t♦♣ ♦❢

t❤❡ ✐♥✐t✐❛❧ s♠❛❧❧ ♠✐❝r♦❝♦❧♦♥✐❡s✱ ❛♥❞ t❤❡ ❤✐❣❤❡st ❝♦♥❝❡♥tr❛t✐♦♥ ♦❢ ❡①tr❛❝❡❧❧✉❧❛r ❉◆❆

✇❛s ♣r❡s❡♥t ❜❡t✇❡❡♥ t❤❡ st❛❧❦✲ ♣♦rt✐♦♥ ❛♥❞ t❤❡ ❝❛♣✲♣♦rt✐♦♥ ♦❢ t❤❡ ♠✉s❤r♦♦♠✲s❤❛♣❡❞

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✺✳✷✳ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✻✾

❋✐❣✉r❡ ✺✳✶✿ ❍♦r✐③♦♥t❛❧ ❝♦♥❢♦❝❛❧ ❧❛s❡r s❝❛♥♥✐♥❣ ♠✐❝r♦s❝♦♣❡ s❡❝t✐♦♥ ❛❝q✉✐r❡❞ ✐♥ ❛ ✷✲

❞❛②✲ ♦❧❞ ❉❉❆❖✲st❛✐♥❡❞ ❜✐♦✜❧♠ ❢♦r♠❡❞ ❜② ●❢♣✲t❛❣❣❡❞ P✳ ❛❡r✉❣✐♥♦s❛ P❆❖✶✳ ❚❤❡

✐♠❛❣❡s s❤♦✇ t❤❡ ❣r❡❡♥ ✢✉♦r❡s❝❡♥t ❜❛❝t❡r✐❛ ✭❆✮✱ t❤❡ r❡❞ ✢✉♦r❡s❝❡♥t ❡①tr❛❝❡❧❧✉❧❛r

❉◆❆ ✭❇✮✱ ❛♥❞ ❛♥ ♦✈❡r❧❛② ♦❢ t❤❡ t✇♦ ✭❈✮✳ ❘❡♣r♦❞✉❝❡❞ ❢r♦♠ ▼♦❧❡❝✉❧❛r ▼✐❝r♦❜✐♦❧♦❣②

✺✾✿ ✶✶✶✹✲✶✶✷✽

♠✉❧t✐❝❡❧❧✉❧❛r str✉❝t✉r❡s✳

❚❤❡ ❢❛❝t♦rs ✐♥✈♦❧✈❡❞ ✇❤❡♥ ❜❛❝t❡r✐❛ s❤✐❢t ❢r♦♠ ❜❡✐♥❣ ♠♦t✐❧❡ t♦ s❡ss✐❧❡ ✐♥ ❜✐♦✜❧♠s ❛r❡

❝✉rr❡♥t❧② ♥♦t ❢✉❧❧② ✉♥❞❡rst♦♦❞✳ ■♥ t❤❡ ♣r❡s❡♥t ❛rt✐❝❧❡ ✇❡ ♣r❡s❡♥t ❛ s✐♠♣❧❡ s♣❛t✐❛❧❧②

❡①♣❧✐❝✐t ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✐♥ ✇❤✐❝❤ ❜❛❝t❡r✐❛❧ ♠♦t✐❧✐t② ✐s r❡❞✉❝❡❞ ❜② ❛ s❡❧❢✲

♣r♦❞✉❝❡❞ ❡①tr❛❝❡❧❧✉❧❛r s✉❜st❛♥❝❡✳

■❇▼s ❤❛✈❡ ❜❡❡♥ ✇✐❞❡❧② ✉s❡❞ ❢♦r ♠♦❞❡❧✐♥❣ s♣❛t✐❛❧ ♦r❣❛♥✐③❛t✐♦♥ ♦❢ ❜❛❝t❡r✐❛ ✇✐t❤✐♥

❝♦❧♦♥✐❡s ❬❑r❡❢t ✷✵✵✶❪ ❬●✐♥♦✈❛rt ✷✵✵✷❪ ❛♥❞ ❜✐♦✜❧♠s ❬❑r❡❢t ✷✵✵✶❪❬❳❛✈✐❡r ✷✵✵✺❪ ✭❢♦r

❛ r❡✈✐❡✇ s❡❡ ❬❋❡rr❡r ✷✵✵✽❪ ❛♥❞ ❬❍❡❧❧✇❡❣❡r ✷✵✵✾❪✮✳ ❘❡❝❡♥t❧②✱ ❛♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧ ♦❢ s✉r❢❛❝❡ ❛ss♦❝✐❛t❡❞ ♣♦♣✉❧❛t✐♦♥s ♦❢ P✳ ❛❡r✉❣✐♥♦s❛ ❤❛s ❜❡❡♥ ♣r❡s❡♥t❡❞

❬P✐❝✐♦r❡❛♥✉ ✷✵✵✼❪✳ ❚❤❡ ♠♦❞❡❧ ✐♥✈♦❧✈❡s ❛ t❤r❡❡✲❞✐♠❡♥s✐♦♥❛❧ s♣❛❝❡ ❛♥❞ ❛✐♠s t♦ ♣r♦✲

✈✐❞❡ ❛ ♣r♦♦❢✲♦❢✲ ♣r✐♥❝✐♣❧❡ ♦❢ t❤❡ ✐♠♣❧✐❝❛t✐♦♥ ♦❢ ♠♦t✐❧✐t② ✐♥ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❜✐♦✜❧♠

str✉❝t✉r❡✳ ■t r❡♣r♦❞✉❝❡s q✉❛❧✐t❛t✐✈❡❧② t❤❡ t❡♥❞❡♥❝② ♦❢ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ t♦ ❢♦r♠ ✢❛t

❜✐♦✜❧♠s ❛♥❞ t❤❛t ♦❢ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛ t♦ ❢♦r♠ ♠✐❝r♦❝♦❧♦♥✐❡s ❜② ❝❧♦♥❛❧ ❣r♦✇t❤✱ ❛♥❞

♣r♦♣♦s❡s ❞❡t❛❝❤♠❡♥t ❛♥❞ r❡❛tt❛❝❤♠❡♥t ♣r♦❝❡ss❡s ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ❛s ♣♦ss✐❜❧❡

♠❡❝❤❛♥✐s♠s ②✐❡❧❞✐♥❣ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦♠♣❧❡① ♠✉s❤r♦♦♠✲s❤❛♣❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s✳ ■♥

♦✉r ♠♦❞❡❧✱ ✇❡ ❢♦❝✉s ♦♥ t❤❡ ✐♥t❡r♣❧❛② ❜❡t✇❡❡♥ ❡①tr❛❝❡❧❧✉❧❛r ❉◆❆ ♣r♦❞✉❝t✐♦♥ ❛♥❞

❜❛❝t❡r✐❛❧ ♠♦t✐❧✐t②✳ ❲❡ s❤♦✇ t❤❛t ❛ ♠♦❞❡❧ ✇❤❡r❡ ❜❛❝t❡r✐❛❧ ♠✐❣r❛t✐♦♥ ✐s st♦♣♣❡❞ ❞✉❡

t♦ ❛❞❤❡r❡♥❝❡ t♦ s❡❧❢✲♣r♦❞✉❝❡❞ ❡①tr❛❝❡❧❧✉❧❛r ❉◆❆ ❝❛♥ ♣r♦❞✉❝❡ ❝♦♠♣❧❡① ♣❛tt❡r♥s ♦❢

✐♥t❡r❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s✳

✺✳✷ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥

❲❡ ❞❡s❝r✐❜❡ t❤❡ ♠♦❞❡❧ t❤r♦✉❣❤ t❤❡ ❖❉❉ ♣r♦t♦❝♦❧ ✭❖✈❡r✈✐❡✇✱ ❉❡s✐❣♥ ❝♦♥❝❡♣ts ❛♥❞

❉❡t❛✐❧s✮ ❬●r✐♠♠ ✷✵✵✻❪✳

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✼✵

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

❋✐❣✉r❡ ✺✳✷✿ ❙❝❤❡♠❛t✐❝ r❡♣r❡s❡♥t❛t✐♦♥ ♦❢ t❤❡ ♠♦❞❡❧ ❡♥t✐t✐❡s✿ ❜❛❝t❡r✐❛❧ ❝❡❧❧s ✭❞✐s❝s✮

❛♥❞ ♣❛t❝❤❡s ✭sq✉❛r❡s ✇✐t❤ ❛ s✐❞❡ ∆l✮✳ ❆ ❜❛❝t❡r✐✉♠ ✇✐t❤ ❝♦♥t✐♥✉♦✉s ❝♦♦r❞✐♥❛t❡s x✱y

✐s ❝♦♥t❛✐♥❡❞ ✐♥ t❤❡ ♣❛t❝❤ i = floor(x/∆l)✱ j = floor(y/∆l)✳

✺✳✷✳✶ P✉r♣♦s❡

❚❤❡ ♠♦❞❡❧ ✇❡ ♣r♦♣♦s❡ ✐s ✐♥t❡♥❞❡❞ t♦ q✉❛❧✐t❛t✐✈❡❧② ❡①♣❧♦r❡ t❤❡ r♦❧❡ ♦❢ s✉r❢❛❝❡✲

♠♦t✐❧✐t② r❡❞✉❝t✐♦♥ ❜② s❡❧❢✲♣r♦❞✉❝❡❞ ♠❛❝r♦♠♦❧❡❝✉❧❡s ✐♥ ❜✐♦✜❧♠ ♣❛tt❡r♥ ❢♦r♠❛t✐♦♥✳

❲❡ ❛❞❞r❡ss t❤✐s q✉❡st✐♦♥ ❛t ❛ r❛t❤❡r ❛❜str❛❝t ❧❡✈❡❧✱ ❛♥❞ t❤❡ ♠♦❞❡❧ r❡s✉❧ts ❛r❡ ♥♦t

❝♦♠♣❛r❡❞ t♦ s♣❡❝✐✜❝ ❡①♣❡r✐♠❡♥t❛❧ r❡s✉❧ts✳

✺✳✷✳✷ ❙t❛t❡ ✈❛r✐❛❜❧❡s ❛♥❞ s❝❛❧❡s

❚❤❡ ♠♦❞❡❧ ✐s ❛ t✇♦✲❞✐♠❡♥s✐♦♥❛❧ r❡♣r❡s❡♥t❛t✐♦♥ ♦❢ ❛ ❜✐♦✜❧♠ s②st❡♠ ❛♥❞ ❝♦♠♣r✐s❡s

t✇♦ ❡♥t✐t✐❡s✿ ❜❛❝t❡r✐❛❧ ❝❡❧❧s ❛♥❞ t❤❡✐r ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ✭♣❛t❝❤❡s✮ ✭✜❣✉r❡ ✺✳✷✮✳ ❇❛❝✲

t❡r✐❛❧ ❝❡❧❧s ❛r❡ r❡♣r❡s❡♥t❡❞ ❛s ❞✐s❝s✳ ❚❤❡② ❛r❡ ❝❤❛r❛❝t❡r✐③❡❞ ❜② t❤❡ st❛t❡ ✈❛r✐❛❜❧❡s✿

❝♦♥t✐♥✉♦✉s ♣♦s✐t✐♦♥ (x, y)✱ ✐♥❞✐✈✐❞✉❛❧ ♠❛ss (m)✱ ✐♥❞✐✈✐❞✉❛❧ ❞✐✛✉s✐♦♥ ❢❛❝t♦r (Df ) ❛♥❞

✐♥❞✐✈✐❞✉❛❧ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡ (r)✭t❛❜❧❡ ✺✳✶✮✳ ❆ P❛t❝❤ (i, j) ✐s ❝❤❛r❛❝t❡r✐③❡❞ ❜② t❤❡

st❛t❡ ✈❛r✐❛❜❧❡s✿ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ (s)✱ ❡①tr❛❝❡❧❧✉❧❛r s✉❜st❛♥❝❡ ❝♦♥❝❡♥tr❛t✐♦♥

(p) ❛♥❞ ❛ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡ (rs)✳ ❚❤❡ ❧❛t❡r ❝♦rr❡s♣♦♥❞s t♦ t❤❡ s✉♠ ♦❢ ✉♣t❛❦❡

r❛t❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❝♦♥t❛✐♥❡❞ ✇✐t❤✐♥ t❤❡ ♣❛t❝❤ ✭t❛❜❧❡ ✺✳✶✮✳

✺✳✷✳✸ ❙❝❛❧❡s

❲❡ s✐♠✉❧❛t❡❞ t❤❡ ✜rst ❞❛② ♦❢ t❤❡ ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t✳ ❲❡ ❞✐s❝r❡t✐③❡❞ t✐♠❡ ✇✐t❤ ❛

❝♦♥st❛♥t t✐♠❡ st❡♣✱ ❞❡♥♦t❡❞ ∆t = 1s✳ ❆ s♣❛t✐❛❧ ♣❛t❝❤ ❤❛s ❛ s✐③❡ ♦❢ 5 × 5 µm ❛♥❞

t❤❡ ✇❤♦❧❡ ❞♦♠❛✐♥ ❝♦♥t❛✐♥s 400 × 400 ♣❛t❝❤❡s ✭s♣❛t✐❛❧ ❞♦♠❛✐♥ s✐❞❡ l = 2000µm✮✳

❇❛❝t❡r✐❛❧ ❝❡❧❧s ❤❛✈❡ ✈❛r✐❛❜❧❡ ❞✐❛♠❡t❡rs (∼ 2µm) ❞❡♣❡♥❞✐♥❣ ♦♥ t❤❡✐r ♠❛ss❡s✳

✺✳✷✳✹ Pr♦❝❡ss ♦✈❡r✈✐❡✇ ❛♥❞ s❝❤❡❞✉❧✐♥❣

■♥ t❤❡ ■❇▼✱ ❜❛❝t❡r✐❛ ♠♦✈❡ st♦❝❤❛st✐❝❛❧❧② ❛❧♦♥❣ ❛ ✷✲❉ s✉r❢❛❝❡ ✇❤✐❧❡ ❝♦♥s✉♠✐♥❣

s✉❜str❛t❡✱ ❣r♦✇✐♥❣ ❛♥❞ r❡♣r♦❞✉❝✐♥❣ ❜② ❜✐♥❛r② ✜ss✐♦♥ ❛♥❞ ❡①❝r❡t✐♥❣ ❛ ♣r♦❞✉❝t✳ ❇❛❝✲

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✺✳✷✳ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✼✶

❱❛r✐❛❜❧❡ ❉❡s❝r✐♣t✐♦♥

❇❛❝t❡r✐✉♠ st❛t❡ x✱ y ❈♦♥t✐♥✉♦✉s ♣♦s✐t✐♦♥ ♦❢ t❤❡ ❝❡♥t❡r ♦❢

t❤❡ ❜❛❝t❡r✐✉♠

m ▼❛ss

Df ❉✐✛✉s✐♦♥ ❢❛❝t♦r

r ■♥❞✐✈✐❞✉❛❧ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡

P❛t❝❤ st❛t❡ s ❙✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥

p ❊①❝r❡t❡❞ ♣r♦❞✉❝t ❝♦♥❝❡♥tr❛t✐♦♥

rs ❘❡❛❝t✐♦♥ r❛t❡ ✭s✉♠ ♦❢ s✉❜str❛t❡ ✉♣✲

t❛❦❡ r❛t❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❝♦♥✲

t❛✐♥❡❞ ✇✐t❤✐♥ t❤❡ ♣❛t❝❤✮

❚❛❜❧❡ ✺✳✶✿ ❙t❛t❡ ✈❛r✐❛❜❧❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

t❡r✐❛ ♠♦✈❡♠❡♥t ✐s t❤❡♥ s❧♦✇❡❞ ❞♦✇♥ t❤r♦✉❣❤ ✐♥t❡r❛❝t✐♦♥s ✇✐t❤ t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t

②✐❡❧❞✐♥❣ ❞✐✛❡r❡♥t ♣❛tt❡r♥s ♦❢ ♠✐❝r♦❝♦❧♦♥✐❡s✳

❆t ❡❛❝❤ t✐♠❡ st❡♣ t❤❡ ❢♦❧❧♦✇✐♥❣ ♣r♦❝❡ss❡s ❛r❡ ♣❡r❢♦r♠❡❞ s❡q✉❡♥t✐❛❧❧②✿

• ❇❛❝t❡r✐❛ ❣r♦✇t❤✿ ❢♦r ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧ ✇❡ ✭✶✮ ❝❛❧❝✉❧❛t❡ ❛♥❞ ✐♥❞✐✈✐❞✉❛❧ s✉❜✲

str❛t❡ ✉♣t❛❦❡ r❛t❡ (r) ✇❤✐❝❤ ❞❡♣❡♥❞s ♦♥ t❤❡ ♠❛ss ♦❢ t❤❡ ❝❡❧❧ ❛♥❞ t❤❡ ❧♦❝❛❧

s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥✳ ✭✷✮ ❲❡ ✉s❡ t❤❡ ❝❛❧❝✉❧❛t❡❞ ✉♣t❛❦❡ r❛t❡ t♦ ✉♣❞❛t❡ t❤❡

♠❛ss ♦❢ t❤❡ ❝❡❧❧✳

• ❙✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡s ❢♦r ♣❛t❝❤❡s✿ ❣✐✈❡♥ t❤❡ ✉♣t❛❦❡ r❛t❡s ♦❢ ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧

❝❡❧❧✱ ✇❡ ❝❛❧❝✉❧❛t❡ ❛♥ ✉♣t❛❦❡ r❛t❡ (rs) ❢♦r ❡❛❝❤ ♣❛t❝❤ ❜② t❛❦✐♥❣ t❤❡ s✉♠ ♦❢ t❤❡

✉♣t❛❦❡ r❛t❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❝♦♥t❛✐♥❡❞ ✇✐t❤✐♥ ✐t✳

• ❉✐✈✐s✐♦♥✿ ❢♦r ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧ ✇❡ ❝♦♠♣❛r❡ t❤❡ ❝❡❧❧ ♠❛ss t♦ ❛ ❝r✐t✐❝❛❧ ✈❛❧✉❡✳

■❢ t❤❡ ❝❡❧❧ ♠❛ss ✐s ❤✐❣❤❡r t❤❛♥ t❤❡ ❝r✐t✐❝❛❧ ✈❛❧✉❡ t❤❛♥ t❤❡ ❝❡❧❧ ✐s ❞✐✈✐❞❡❞ ✐♥t♦

t✇♦ ❞❛✉❣❤t❡r ❝❡❧❧s✳ ❖♥❡ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧s t❛❦❡s t❤❡ ♣♦s✐t✐♦♥ ♦❢ t❤❡ ♠♦t❤❡r

❝❡❧❧ ✇❤✐❧❡ t❤❡ s❡❝♦♥❞ ✐s ♣❧❛❝❡❞ ❛t r❛♥❞♦♠ ❛r♦✉♥❞ t❤❡ ♠♦t❤❡r ❝❡❧❧ ♣♦s✐t✐♦♥ ❛t

❛ ❞✐st❛♥❝❡ (d) ❝♦rr❡s♣♦♥❞✐♥❣ t♦ t❤❡ ❞✐❛♠❡t❡r ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧✳

• ❙✉r❢❛❝❡ ♠♦t✐❧✐t②✿ ✇❡ ♠♦❞❡❧ ❜❛❝t❡r✐❛ tr❛♥s❧♦❝❛t✐♦♥ ❛s ❛ ❇r♦✇♥✐❛♥ ♣r♦❝❡ss ✉s✐♥❣

❛♥ ❞✐✛✉s✐♦♥ ❢❛❝t♦r (Df ) ♣r♦♣❡r t♦ ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧✳ ❋♦r ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧✱

✐♥❝❧✉❞✐♥❣ ♥❡✇❧② ❢♦r♠❡❞ ❝❡❧❧s✱ ✇❡ ❝❛❧❝✉❧❛t❡ ❛ ❞✐✛✉s✐♦♥ ❢❛❝t♦r ✭Df ✮ ✉s✐♥❣ ❛

❞❡❝r❡❛s✐♥❣ ❢✉♥❝t✐♦♥ ♦❢ t❤❡ ❧♦❝❛❧ ♣r♦❞✉❝t ❝♦♥❝❡♥tr❛t✐♦♥ ❛♥❞ t❤❡♥ ♠♦✈❡ t❤❡

✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧ ❛❝❝♦r❞✐♥❣❧②✳

• ❙❤♦✈✐♥❣✿ ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥ ❛♥❞ ♠♦t✐♦♥ ♠❛② ♣r♦❞✉❝❡ ❝❡❧❧s ♦✈❡r❧❛♣s✳ ■♥ t❤✐s ❝❛s❡

❝❡❧❧s ❛r❡ ❞✐s♣❧❛❝❡❞ ✉s✐♥❣ ❛♥ ❛❧❣♦r✐t❤♠ ♣r♦♣♦s❡❞ ❜② ❬❑r❡❢t ✷✵✵✶❪t❤❛t ♠✐♠✐❝s ❛

s❤♦✈✐♥❣ ♣r♦❝❡ss✳

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✼✷

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

• ❙✉❜str❛t❡ ❛♥❞ ❡①❝r❡t❡❞ ♣r♦❞✉❝t ♠❛ss ❜❛❧❛♥❝❡s✿ ✇❡ ♠♦❞❡❧❡❞ t❤❡ s✉❜str❛t❡

❛♥❞ t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t ❞②♥❛♠✐❝s ✉s✐♥❣ t✇♦ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ❡q✉❛t✐♦♥s ❞✐s✲

❝r❡t✐③❡❞ ♦♥ t❤❡ ❧❛tt✐❝❡ ❢♦r♠❡❞ ❜② t❤❡ ♣❛t❝❤❡s✳ ❚❤❡ r❡❛❝t✐♦♥ t❡r♠s ✐♥ t❤❡s❡

❡q✉❛t✐♦♥s ❛r❡ ❝❛❧❝✉❧❛t❡❞ ✉s✐♥❣ t❤❡ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡ (rs) ♣r❡✈✐♦✉s❧② ❝❛❧✲

❝✉❧❛t❡❞ ❢♦r ❡❛❝❤ ♣❛t❝❤✳

✺✳✷✳✺ ❉❡s✐❣♥ ❈♦♥❝❡♣ts

• ❊♠❡r❣❡♥❝❡✿ t❤❡ ■❇▼ ✐s ❞❡s✐❣♥❡❞ s✉❝❤ t❤❛t t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ♦❢ ❜❛❝t❡r✐❛ ❛♥❞

♣r♦❞✉❝t ❞✐str✐❜✉t✐♦♥ ❡♠❡r❣❡ ❢r♦♠ ❧♦❝❛❧ ✐♥t❡r❛❝t✐♦♥s✳

• ❙❡♥s✐♥❣✿ ✐♥ ♦✉r ♠♦❞❡❧✱ ❛ ❜❛❝t❡r✐✉♠ s❡♥s❡s t❤❡ s✉❜str❛t❡ ❛♥❞ ♣r♦❞✉❝t ❝♦♥❝❡♥✲

tr❛t✐♦♥ ✇✐t❤✐♥ t❤❡ ♣❛t❝❤ ❝♦rr❡s♣♦♥❞✐♥❣ t♦ ✐ts ♣♦s✐t✐♦♥✳ ❚❤❡ s✉❜str❛t❡ ❝♦♥❝❡♥✲

tr❛t✐♦♥ ❛✛❡❝ts t❤❡ ❣r♦✇t❤ r❛t❡ ♦❢ t❤❡ ❜❛❝t❡r✐✉♠ ✇❤❡r❡❛s t❤❡ ♣r♦❞✉❝t ❝♦♥❝❡♥✲

tr❛t✐♦♥ ❛✛❡❝ts t❤❡ ♠♦t✐❧✐t② ♦❢ t❤❡ ❜❛❝t❡r✐❛✳

• ❙t♦❝❤❛st✐❝✐t②✿ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② ❛♥❞ t❤❡ ♣♦s✐t✐♦♥✐♥❣ ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧s ❛❢t❡r

❛ ❞✐✈✐s✐♦♥ ❡✈❡♥t ❛r❡ t❤❡ ♦♥❧② st♦❝❤❛st✐❝ ♣r♦❝❡ss❡s t❤❛t ✇❡ ❝♦♥s✐❞❡r❡❞ ✐♥ t❤❡

■❇▼✳

• ❖❜s❡r✈❛t✐♦♥✿ ❛t ❡❛❝❤ t✐♠❡ st❡♣ t❤❡ st❛t❡ ✈❛r✐❛❜❧❡s ❢♦r ❜❛❝t❡r✐❛ ❛♥❞ ♣❛t❝❤❡s ❛r❡

r❡❝♦r❞❡❞✳

✺✳✷✳✻ ❙✉❜♠♦❞❡❧s

✺✳✷✳✻✳✶ ❇❛❝t❡r✐❛ ❣r♦✇t❤

❲❡ ❝❛❧❝✉❧❛t❡ t❤❡ ✐♥❞✐✈✐❞✉❛❧ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡ (r(t)) ♦❢ ❛ ❝❡❧❧ ❧♦❝❛t❡❞ ✐♥ (x, y)

❛♥❞ ❤❛✈✐♥❣ ❛ ♠❛ss m ✉s✐♥❣ t❤❡ ❢♦❧❧♦✇✐♥❣ ▼♦♥♦❞✲❧✐❦❡ ❦✐♥❡t✐❝ ❡q✉❛t✐♦♥✿

r(t) = µmaxms(i, j, t)

s(i, j, t) + ks✭✺✳✶✮

❲❤❡r❡ s(i, j, t) ✐s t❤❡ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ❛t ♣❛t❝❤ ✭i, j) ✇✐t❤ i = floor(x/∆l)

❛♥❞ j = floor(y/∆l) ❛♥❞ µmax ❛♥❞ ks ❛r❡ ▼♦♥♦❞ ❦✐♥❡t✐❝ ♣❛r❛♠❡t❡rs✳ ❚❤❡ ❣r♦✇t❤

r❛t❡ ♦❢ t❤❡ ❜❛❝t❡r✐✉♠ ✐s ❣✐✈❡♥ ❜②✿

dm

dt= Ybr(t) ✭✺✳✷✮

❲❤❡r❡ Y b ✐s t❤❡ ❜✐♦♠❛ss ②✐❡❧❞ ✭❡①♣r❡ss❡❞ ✐♥ ♠❛ss ♦❢ ❜❛❝t❡r✐❛ ♣❡r ♠❛ss ♦❢ ❝♦♥✲

s✉♠❡❞ s✉❜str❛t❡✮✳ ❚❤❡ t✐♠❡ ❞❡r✐✈❛t✐✈❡ ✐s ❞✐s❝r❡t✐③❡❞ ✉s✐♥❣ ❛♥ ❊✉❧❡r ❡①♣❧✐❝✐t s❝❤❡♠❡

❛♥❞ t❤❡ ♥❡✇ ♠❛ss ♦❢ t❤❡ ❝❡❧❧ ✐s ❝❛❧❝✉❧❛t❡❞ ❜②✿

m(t+∆t) = m(t) + ∆tYbr(t) ✭✺✳✸✮

❲✐t❤ ∆t t❤❡ t✐♠❡ st❡♣✳ ❚❤❡ ♣r♦❞✉❝t ❡①❝r❡t✐♦♥ r❛t❡ rp(t) ♦❢ t❤❡ ❝♦♥s✐❞❡r❡❞

✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧ ✐s ❣✐✈❡♥ ❜②✿

rp(t) = Ypr(t) ✭✺✳✹✮

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✺✳✷✳ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✼✸

✺✳✷✳✻✳✷ ❙✉❜str❛t❡ ❯♣t❛❦❡ r❛t❡s

❋♦r ❡❛❝❤ ♣❛t❝❤ ✇❡ ❝❛❧❝✉❧❛t❡ ❛ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡ rs(t, i, j) ❜② s✉♠♠✐♥❣ t❤❡ ✐♥❞✐✲

✈✐❞✉❛❧ s✉❜str❛t❡ ✉♣t❛❦❡ r❛t❡s ♦❢ t❤❡ ❝❡❧❧s ❝♦♥t❛✐♥❡❞ ✇✐t❤✐♥ t❤❡ ♣❛t❝❤✿

rs(t, i, j) =1

∆l2

k

rk(t) ✭✺✳✺✮

✇❤❡r❡ k ✐s t❤❡ ♥✉♠❜❡r ♦❢ ❝❡❧❧s ✐♥ ♣❛t❝❤ i, j✳

✺✳✷✳✻✳✸ ❇❛❝t❡r✐❛ ❞✐✈✐s✐♦♥

■❢ t❤❡ ♠❛ss ♦❢ ❛ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧ ✭❛ ♠♦t❤❡r ❝❡❧❧✮ ❜❡❝♦♠❡s ❣r❡❛t❡r t❤❛♥ t✇✐❝❡ t❤❡ ✐♥✐t✐❛❧

♠❛ss ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧ (2m0 ≤ m) ✐t ❞✐✈✐❞❡s ✐♥t♦ t✇♦ ❞❛✉❣❤t❡r ❝❡❧❧s ❡❛❝❤ ✇✐t❤ ❛ ♠❛ss

m/2✳ ❚❤❡ ✜rst ❞❛✉❣❤t❡r ❝❡❧❧ t❛❦❡s t❤❡ ♣♦s✐t✐♦♥ ♦❢ t❤❡ ♠♦t❤❡r ❝❡❧❧ ✇❤✐❧❡ t❤❡ s❡❝♦♥❞

❞❛✉❣❤t❡r ❝❡❧❧ ✐s ♣❧❛❝❡❞ r❛♥❞♦♠❧② ❛t ❛ ❞✐st❛♥❝❡ ❞ ✭❞✐st❛♥❝❡ ❜❡t✇❡❡♥ t❤❡ ❝❡♥t❡rs ♦❢

❜♦t❤ ❝❡❧❧s✮ ❝♦rr❡s♣♦♥❞✐♥❣ t♦ t❤❡ ❞✐❛♠❡t❡r ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧s ✭❜♦t❤ ❞❛✉❣❤t❡r ❝❡❧❧s

❤❛✈❡ t❤❡ s❛♠❡ ❞✐❛♠❡t❡r✮✳

✺✳✷✳✻✳✹ ❇❛❝t❡r✐❛ ♠♦t✐❧✐t②

❚❤❡ ♠♦t✐❧✐t② ♦❢ t❤❡ ❝❡❧❧s ✐s ♠♦❞❡❧❡❞ ❛s ❛ ❇r♦✇♥✐❛♥ ♠♦t✐♦♥ ♣r♦❝❡ss ✇✐t❤ ❛♥ ❛♣♣❛r❡♥t

❞✐✛✉s✐♦♥ ❢❛❝t♦r (Df) ✇❤✐❝❤ ✐s s♣❡❝✐✜❝ t♦ ❡❛❝❤ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧✳ ❋♦r ❛ ❣✐✈❡♥ ❜❛❝t❡r✐✉♠

❧♦❝❛t❡❞ ❛t x, y ❛t t✐♠❡ t✱ t❤❡ ♣♦s✐t✐♦♥ ♦❢ t❤❡ ❜❛❝t❡r✐✉♠ ❛t t❤❡ ✐♥st❛♥t t+∆t ✐s ❣✐✈❡♥

❜②✿

x(t+∆t) = x(t) +√

2Df (x, y)∆tN(0, 1) ✭✺✳✻✮

y(t+∆t) = y(t) +√

2Df (x, y)∆tN(0, 1)

✇❤❡r❡ N(0, 1) ❞r❛✇s ❛ ♥✉♠❜❡r ❢r♦♠ ❛ ❝❡♥t❡r❡❞ ♥♦r♠❛❧ ❞✐str✐❜✉t✐♦♥ ♦❢ st❛♥❞❛r❞

❞❡✈✐❛t✐♦♥ 1 ✭❣❡♥❡r❛t❡❞ ✉s✐♥❣ t❤❡ ▼❡rs❡♥♥❡ ❚✇✐st❡r ♣s❡✉❞♦✲r❛♥❞♦♠ ♥✉♠❜❡r ❣❡♥❡r✲

❛t♦r✮✳ ❆s ✇❡ ❛ss✉♠❡❞ t❤❛t ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② ✇❛s r❡❞✉❝❡❞ ❜② t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t✱

✇❡ ❝❛❧❝✉❧❛t❡ ❞✐✛✉s✐♦♥ ❢❛❝t♦r (Df ) ❛s ❛ ❞❡❝r❡❛s✐♥❣ ❢✉♥❝t✐♦♥ ♦❢ t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t

❝♦♥❝❡♥tr❛t✐♦♥ ✐♥ t❤❡ ❝♦rr❡s♣♦♥❞✐♥❣ ♣❛t❝❤ (i, j)✳ ❲❡ ✉s❡ t❤❡ ❢♦❧❧♦✇✐♥❣ ❢✉♥❝t✐♦♥✿

Df = Dfmax1

1 + βp(i, j, t)✭✺✳✼✮

❲❤❡r❡ Dfmax ✐s t❤❡ ♠❛①✐♠✉♠ ❞✐✛✉s✐♦♥ ❢❛❝t♦r ♦❢ t❤❡ ❜❛❝t❡r✐✉♠✱ β ✐s ❛ ❜✐♥❞✐♥❣

❛✣♥✐t② ❢❛❝t♦r ❛♥❞ p(i, j, t) ✐s t❤❡ ♣r♦❞✉❝t ❝♦♥❝❡♥tr❛t✐♦♥ ❛t ♣❛t❝❤ (i, j)✳ ❚❤❡ ♣❛r❛♠✲

❡t❡r β r✉❧❡s t❤❡ s❡♥s✐t✐✈✐t② ♦❢ Df t♦ t❤❡ ✈❛r✐❛t✐♦♥ ♦❢ p(i, j, t) ❛s s❤♦✇♥ ❜② ✜❣✉r❡

✺✳✸✳

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✼✹

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

❋✐❣✉r❡ ✺✳✸✿ ▼♦t✐❧✐t② ❞❡♣❡♥❞❡♥❝❡ ♦♥ t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t ❝♦♥❝❡♥tr❛t✐♦♥ ❢♦r ❞✐✛❡r❡♥t

✈❛❧✉❡s ♦❢ β

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✺✳✷✳ ▼♦❞❡❧ ❞❡s❝r✐♣t✐♦♥ ✼✺

✺✳✷✳✻✳✺ ❇❛❝t❡r✐❛ s❤♦✈✐♥❣

❇❛❝t❡r✐❛ s❤♦✈❡ ❡❛❝❤ ♦t❤❡r ✇❤❡♥ t❤❡② ♦✈❡r❧❛♣✳ ■❢ ❛ ❜❛❝t❡r✐✉♠ ✇✐t❤ r❛❞✐✉s a ✐s ♦✈❡r✲

❧❛♣♣❡❞ ✇✐t❤ n ♥❡✐❣❤❜♦r✐♥❣ ❝❡❧❧s✱ ✐t ✐s ❞✐s♣❧❛❝❡❞ ✇✐t❤ ❛ s❤♦✈✐♥❣ ✈❡❝t♦r d ❝❛❧❝✉❧❛t❡❞

✉s✐♥❣ t❤❡ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥ ❛❞❛♣t❡❞ ❢r♦♠ ❬❑r❡❢t ✷✵✵✶❪✿

d =∑

k=1:n

a+ ak − dk2

uk ✭✺✳✽✮

ak ✐s t❤❡ r❛❞✐✉s ♦❢ t❤❡ ♥❡✐❣❤❜♦r ❝❡❧❧ k✱ dk ✐s t❤❡ ❊✉❝❧✐❞❡❛♥ ❞✐st❛♥❝❡ ❢r♦♠ t❤❡

❝❡♥t❡r ♦❢ t❤❡ ❜❛❝t❡r✐✉♠ t♦ t❤❡ ❝❡♥t❡r t❤❡ kth ♥❡✐❣❤❜♦r✐♥❣ ❝❡❧❧ ❛♥❞ uk ✐s ❛ ✈❡❝t♦r

❞✐r❡❝t❡❞ ❢r♦♠ t❤❡ ❝❡♥t❡r ♦❢ ♥❡✐❣❤❜♦r ❜❛❝t❡r✐✉♠ k t♦✇❛r❞s t❤❡ ❝❡♥t❡r ♦❢ t❤❡ ❜❛❝t❡r✐✉♠

❛♥❞ ❤❛✈✐♥❣ ❛ ✉♥✐t❛r② ♥♦r♠✳

✺✳✷✳✻✳✻ ❙✉❜str❛t❡ ❛♥❞ ❡①❝r❡t❡❞ ♣r♦❞✉❝t ♠❛ss ❜❛❧❛♥❝❡ ❡q✉❛t✐♦♥

❚❤❡ ❞✐str✐❜✉t✐♦♥ ♦❢ t❤❡ s✉❜str❛t❡ ✐s t❤❡ s♦❧✉t✐♦♥ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝♦♥t✐♥✉♦✉s ❞✐✛✉s✐♦♥✲

r❡❛❝t✐♦♥ ❡q✉❛t✐♦♥✿

∂s

∂t= Ds∇

2s− rs ✭✺✳✾✮

✇✐t❤ ♣❡r✐♦❞✐❝ ❜♦✉♥❞❛r② ❝♦♥❞✐t✐♦♥s✿

s(t, x = 0, y) = s(t, x = l, y) ✭✺✳✶✵✮

s(t, x, y = 0) = s(t, x, y = l) ✭✺✳✶✶✮

❛♥❞ ❤❛✈✐♥❣ ❛s ✐♥✐t✐❛❧ ❝♦♥❞✐t✐♦♥s✿

s(t = 0, x, y) = s0 ✭✺✳✶✷✮

❚❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t ❞②♥❛♠✐❝ ✐s ❛❧s♦ ❣✐✈❡♥ ❜② ❛ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ❡q✉❛t✐♦♥✿

∂p

∂t= Dp∇

2p+ Yprs ✭✺✳✶✸✮

✇✐t❤ ♣❡r✐♦❞✐❝ ❜♦✉♥❞❛r② ❝♦♥❞✐t✐♦♥s✿

p(t, x = 0, y) = p(t, x = l, y) ✭✺✳✶✹✮

p(t, x, y = 0) = p(t, x, y = l) ✭✺✳✶✺✮

❛♥❞ ❤❛✈✐♥❣ ❛s ✐♥✐t✐❛❧ ❝♦♥❞✐t✐♦♥s

p(t = 0, x, y) = 0 ✭✺✳✶✻✮

Yp ✐♥ ✭❡q✉❛t✐♦♥ ✺✳✶✸✮ ✐s t❤❡ ♣r♦❞✉❝t ②✐❡❧❞ ❡①♣r❡ss❡❞ ✐♥ ♠❛ss ♦❢ ❡①❝r❡t❡❞ ♣r♦❞✉❝t

♣❡r ♠❛ss ♦❢ ❝♦♥s✉♠❡❞ s✉❜str❛t❡✳ ❲❡ ❞✐s❝r❡t✐③❡ s✉❜str❛t❡ ❛♥❞ ♣r♦❞✉❝t ♠❛ss ❜❛❧❛♥❝❡

❡q✉❛t✐♦♥s ✇✐t❤ r❡s♣❡❝t t♦ s♣❛❝❡ ♦♥ t❤❡ ❧❛tt✐❝❡ ❢♦r♠❡❞ ✇✐t❤ t❤❡ ♣❛t❝❤❡s ✉s✐♥❣ ❛

❢♦✉r✲♣♦✐♥t s❝❤❡♠❡✳ ❚❤❡ r❡❛❝t✐♦♥ t❡r♠ ❤❛s ❛❧r❡❛❞② ❜❡❡♥ ❝❛❧❝✉❧❛t❡❞ ❢♦r ❡❛❝❤ ♣❛t❝❤

✭❡q✉❛t✐♦♥ ✺✮✳ ❲❡ ❞✐s❝r❡t✐③❡ t✐♠❡ ❞❡r✐✈❛t✐✈❡ t❡r♠ ✐♥ t❤❡ s✉❜str❛t❡ ❛♥❞ t❤❡ ♣r♦❞✉❝t

♠❛ss ❜❛❧❛♥❝❡ ❡q✉❛t✐♦♥s ✉s✐♥❣ ❛♥ ✐♠♣❧✐❝✐t s❝❤❡♠❡ ❢♦r t❤❡ ❞✐✛✉s✐♦♥ t❡r♠✳ ◆♦t❡ t❤❛t

t❤❡ r❡❛❝t✐♦♥ t❡r♠ ✐s ❝❛❧❝✉❧❛t❡❞ ♦♥ t❤❡ ❜❛s✐s ♦❢ ❛♥ ❡①♣❧✐❝✐t s❝❤❡♠❡✳ ❚❤❡ ♦❜t❛✐♥❡❞

❞✐s❝r❡t✐③❡❞ s②st❡♠ ✐s ❛ s♣❛rs❡ ❧✐♥❡❛r s②st❡♠ t❤❛t ✇❡ s♦❧✈❡ ✉s✐♥❣ ❛♥ ❡①♣❧✐❝✐t ❊✉❧❡r

♠❡t❤♦❞✳ ❚❤✐s ❣✐✈❡s t❤❡ ♥❡✇ s✉❜str❛t❡ ❛♥❞ ♣r♦❞✉❝t ❝♦♥❝❡♥tr❛t✐♦♥s ✐♥ ❡❛❝❤ ♣❛t❝❤✳

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✼✻

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

P❛r❛♠❡t❡r ❉❡s❝r✐♣t✐♦♥ ❯♥✐ts ❱❛❧✉❡

l ❉♦♠❛✐♥ s✐③❡ (µm) 2000 ✭✯✮

∆l ❙♣❛t✐❛❧ st❡♣ (µm) 5 ✭✯✮

Ds ❉✐✛✉s✐♦♥ ❝♦♥st❛♥t ❢♦r t❤❡ s✉❜str❛t❡ (m2/s) 10−10 ✭✯✯✮

Dp ❉✐✛✉s✐♦♥ ❝♦♥st❛♥t ❢♦r t❤❡ ♣r♦❞✉❝t (m2/s) 10−16 ✭✯✮

Dfmax ▼❛①✐♠✉♠ ❞✐✛✉s✐♦♥ ❢❛❝t♦r ❢♦r t❤❡ ❜❛❝t❡r✐❛ (m2/s) 10−12 ✭✯✯✮

µmax ▼❛①✐♠✉♠ ❣r♦✇t❤ r❛t❡ kgsubstrate/(kgbiomass s) 10−4 ✭✯✯✮

ks ❆✣♥✐t② ❝♦♥st❛♥t kgsubstrate/m2) 0.01 ✭✯✯✮

Yp Pr♦❞✉❝t ②✐❡❧❞ kgbiomass/kgsubstrate 0.1 ✭✯✮

❚❛❜❧❡ ✺✳✷✿ ❚❛❜❧❡ ✷ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs✳ ❙♦✉r❝❡✿ ✭✯✮❆ss✉♠❡❞ ✲

✭✯✯✮❆❞❛♣t❡❞ ❢r♦♠ ❬P✐❝✐♦r❡❛♥✉ ✷✵✵✼❪

P❛r❛♠❡t❡r ❉❡s❝r✐♣t✐♦♥ ❯♥✐ts ❱❛❧✉❡

s0 ■♥✐t✐❛❧ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ✐♥ ❛❧❧ ♣❛t❝❤❡s kg/m2 ✶✵✳✵

p0 ■♥✐t✐❛❧ ♣r♦❞✉❝t ❝♦♥❝❡♥tr❛t✐♦♥ ✐♥ ❛❧❧ ♣❛t❝❤❡s kg/m2 ✵✳✵

N0 ■♥✐t✐❛❧ ♥✉♠❜❡r ♦❢ ❜❛❝t❡r✐❛❧ ❝❡❧❧s − ✶✵✵

m0 ■♥✐t✐❛❧ ♠❛ss ♦❢ ❛ ❜❛❝t❡r✐✉♠ kg 10−15

❚❛❜❧❡ ✺✳✸✿ ■♥✐t✐❛❧ ❝♦♥❞✐t✐♦♥s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

✺✳✷✳✻✳✼ ■❇▼ ♣❛r❛♠❡t❡rs

❯♥❧❡ss ❡①♣❧✐❝✐t❧② s♣❡❝✐✜❡❞✱ ✇❡ ✉s❡ t❤❡ ♣❛r❛♠❡t❡rs ✈❛❧✉❡s ✐♥ t❛❜❧❡ ✺✳✷ ❢♦r t❤❡

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✳

✺✳✷✳✻✳✽ ■♥✐t✐❛❧✐③❛t✐♦♥

❲❡ ✐♥✐t✐❛❧✐③❡ ❛❧❧ s✐♠✉❧❛t✐♦♥s ✇✐t❤✿

• ❛ ✉♥✐❢♦r♠ ✐♥✐t✐❛❧ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ s0

• ❛ ✉♥✐❢♦r♠❧② ♥✉❧❧ ❝♦♥❝❡♥tr❛t✐♦♥ ♦❢ ❡①❝r❡t❡❞ ♣r♦❞✉❝t

• N0 ❜❛❝t❡r✐❛❧ ❝❡❧❧s ❞r❛✇♥ ❛t r❛♥❞♦♠ ✐♥ t❤❡ ❞♦♠❛✐♥ ❡❛❝❤ ✇✐t❤ t❤❡ s❛♠❡ ✐♥✐t✐❛❧

♠❛ss m0✳

■♥✐t✐❛❧ ❝♦♥❞✐t✐♦♥s ❛r❡ ❞❡t❛✐❧❡❞ ✐♥ t❛❜❧❡ ✺✳✸✳

✺✳✷✳✻✳✾ ▼♦❞❡❧ ✐♠♣❧❡♠❡♥t❛t✐♦♥

❲❡ ✐♠♣❧❡♠❡♥t❡❞ t❤❡ ♠♦❞❡❧ ✉s✐♥❣ t❤❡ ❏❛✈❛ ♣r♦❣r❛♠♠✐♥❣ ❧❛♥❣✉❛❣❡ ❛♥❞ t❤❡ ▼❛s♦♥

❢r❛♠❡✇♦r❦✳ ▼❛s♦♥ ✐s ❛ ❞✐s❝r❡t❡ ❡✈❡♥t ♠✉❧t✐❛❣❡♥t s✐♠✉❧❛t✐♦♥ ❧✐❜r❛r② ❝♦❞❡ ❞❡✈❡❧♦♣❡❞

❛t t❤❡ ●❡♦r❣❡ ▼❛s♦♥ ❯♥✐✈❡rs✐t② ❢♦r ✐♠♣❧❡♠❡♥t✐♥❣ ♠✉❧t✐✲❛❣❡♥t ♠♦❞❡❧s ❬▲✉❦❡ ✷✵✵✹❪✳

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✺✳✸✳ ❘❡s✉❧ts ✼✼

✺✳✸ ❘❡s✉❧ts

❲❡ s✐♠✉❧❛t❡ t❤❡ ♣❛tt❡r♥s ❢♦r♠❡❞ ❜② t❤❡ s♣❛t✐❛❧ ❞✐str✐❜✉t✐♦♥ ♦❢ ❜❛❝t❡r✐❛ ❛♥❞ t❤❡

❡①❝r❡t❡❞ ♣r♦❞✉❝t ❞✐s♣❧❛②❡❞ ❛❢t❡r 9 ❛♥❞ 18 ❤♦✉rs ❢♦r ❞✐✛❡r❡♥t ✈❛❧✉❡s ♦❢ β ✭t❤❡ ♣❛✲

r❛♠❡t❡r ❞❡t❡r♠✐♥✐♥❣ t❤❡ ✐♠♣❛❝t ♦❢ t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t ♦♥ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t②✮ ❛♥❞

❢♦r t❤❡ ❝❛s❡ ♦❢ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛✳ ❚✇♦ ❡①tr❡♠❡ ❝❛s❡s ❝❛♥ ❜❡ ✐❞❡♥t✐✜❡❞✳ ■♥ t❤❡ ✜rst

❝❛s❡✱ ❜❛❝t❡r✐❛ ❛r❡ ♠♦t✐❧❡ ❛♥❞ t❤❡✐r ♠♦t✐❧✐t② ✐s ✐♥❞❡♣❡♥❞❡♥t ❢r♦♠ t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t

(β = 0) ✇❤✐❧❡ ✐♥ t❤❡ s❡❝♦♥❞ ❝❛s❡ ❜❛❝t❡r✐❛ ❛r❡ ✐♠♠♦t✐❧❡ Dfmax = 0✳ ❋✐❣✉r❡s ✹ ❛♥❞ ✺

s❤♦✇ t❤❡ ♣❛tt❡r♥s ♦❜t❛✐♥❡❞ ✐♥ t❤❡s❡ ❧✐♠✐t✐♥❣ ❝❛s❡s✳ ▼♦t✐❧❡ ❝❡❧❧s ❞✐s♣❡rs❡ ♦✈❡r t❤❡ s♣❛✲

t✐❛❧ ❞♦♠❛✐♥ ✭❋✐❣✳ ✹✮ ✐♥ ❝♦♥tr❛st ✇✐t❤ ✐♠♠♦t✐❧❡ ❝❡❧❧s t❤❛t ❢♦r♠ ✐s♦❧❛t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s

✭❋✐❣✳ ✺✮✳ ❚❤❡s❡ r❡s✉❧ts ❛r❡ ❝♦♥s✐st❡♥t ✇✐t❤ ♣r❡✈✐♦✉s t❤❡♦r❡t✐❝❛❧ ❬P✐❝✐♦r❡❛♥✉ ✷✵✵✼❪

❛♥❞ ❡①♣❡r✐♠❡♥t❛❧ ❬❑❧❛✉s❡♥ ✵✵✸❜❪ st✉❞✐❡s ♦❢ P✳ ❛❡r✉❣✐♥♦s❛ s❤♦✇✐♥❣ t❤❛t ♠♦t✐❧❡ ❝❡❧❧s

t❡♥❞ t♦ ❢♦r♠ ✢❛t ❜✐♦✜❧♠s ✇❤✐❧❡ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛ ❢♦r♠ r♦✉♥❞ s❤❛♣❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s✳

❲❡ ❛❧s♦ s✐♠✉❧❛t❡❞ ✐♥t❡r♠❡❞✐❛t❡ ❝❛s❡s ✇❤❡r❡ t❤❡ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② ❞❡♣❡♥❞s ♦♥ t❤❡

❧♦❝❛❧ ❝♦♥❝❡♥tr❛t✐♦♥ ♦❢ t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t✳ ❋✐❣✉r❡ 6 ❛♥❞ 7 s❤♦✇ ❡①❛♠♣❧❡s ♦❢ s♣❛t✐❛❧

♣❛tt❡r♥ ♦❜t❛✐♥❡❞ ❛❢t❡r 9 ❛♥❞ 18 ❤♦✉rs ❢♦r ❛ s♠❛❧❧ ❛♥❞ ❛ ❧❛r❣❡ ✈❛❧✉❡ ♦❢ t❤❡ ♣❛r❛♠❡t❡r

β r❡s♣❡❝t✐✈❡❧②✳ ❆s t❤❡ s②st❡♠ ❡✈♦❧✈❡s ♦✈❡r t✐♠❡✱ t❤❡ ♣❛tt❡r♥s ♦❢ ♠✐❝r♦❝♦❧♦♥② ❢♦r♠❛✲

t✐♦♥ ✉♥❞❡r t❤❡ t✇♦ ♣❛r❛♠❡t❡r✐③❛t✐♦♥s ❜❡❣✐♥ t♦ ❞✐✈❡r❣❡✳ ❆ ❧❛r❣❡ ✈❛❧✉❡ ♦❢ β r❡s✉❧ts

✐♥ ♠✐❝r♦❝♦❧♦♥✐❡s t❤❛t ❛r❡ ♠♦r❡ s♣❛t✐❛❧❧② ❞✐s❝r❡t❡ ✇✐t❤ ❤✐❣❤❡r ❞❡♥s✐t✐❡s ♦❢ ✐♥❞✐✈✐❞✉❛❧s

✇✐t❤✐♥ t❤❡♠ ✭❋✐❣✉r❡ ✺✳✼✮✱ ✇❤✐❧❡ t❤❡ s♠❛❧❧❡r ✈❛❧✉❡ ♦❢ β r❡s✉❧ts ✐♥ ❛ ♣❛tt❡r♥ ♦❢ ♠✐❝r♦✲

❝♦❧♦♥✐❡s t❤❛t ❛r❡ ♠♦r❡ ❛♠♦r♣❤♦✉s ✐♥ s✐③❡ ❛♥❞ s❤❛♣❡✱ ❛r❡ ♠♦r❡ ❝♦♥♥❡❝t❡❞ ✇✐t❤ ❡❛❝❤

♦t❤❡r✱ ❛♥❞ ❞❡♥s✐t✐❡s ♦❢ ❜❛❝t❡r✐❛ ✇✐t❤✐♥ t❤❡♠ ❛r❡ ❧♦✇❡r ✭❋✐❣✉r❡ ✺✳✻✮✳

■♥ ♦✉r s✐♠✉❧❛t✐♦♥s✱ ♠✐❝r♦❝♦❧♦♥② ❢♦r♠❛t✐♦♥ ✐s ✐♥✐t✐❛t❡❞ ❜② t❤❡ ❧♦❝❛❧ ❛❝❝✉♠✉❧❛t✐♦♥

♦❢ t❤❡ ♣r♦❞✉❝t ❡①❝r❡t❡❞ ❜② t❤❡ ❝❡❧❧s ❛❧♦♥❣ t❤❡✐r ❇r♦✇♥✐❛♥ tr❛❥❡❝t♦r✐❡s✳ ❚❤❡ ♣r♦❞✉❝t

❡①❝r❡t✐♦♥ r❛t❡ ✐s ♠❛①✐♠❛❧ ✭∼ Ypµmax✱ s❡❡ ❊q✉❛t✐♦♥s ✺✳✶ ❛♥❞ ✺✳✼✮ ❛t t❤❡ ❜❡❣✐♥♥✐♥❣

♦❢ t❤❡ s✐♠✉❧❛t✐♦♥ ✇❤❡♥ t❤❡ s✉❜str❛t❡ ✭S >> ks ✐♥ ❊q✉❛t✐♦♥ ✶✮ ✐s ❛❜✉♥❞❛♥t ❛♥❞

❛❝❝✉♠✉❧❛t❡s ❞✉❡ t♦ ✐ts ❧♦✇ ❞✐✛✉s✐♦♥ ❢❛❝t♦r✳ ❋♦r ❧❛r❣❡ ✈❛❧✉❡s ♦❢ β ❜❛❝t❡r✐❛ ❛r❡ r❛♣✐❞❧②

❡♥tr❛♣♣❡❞ ✇✐t❤✐♥ t❤❡ ❧♦❝❛t✐♦♥s ❝♦♥t❛✐♥✐♥❣ t❤❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t ❛♥❞ t❤❡✐r ❞❛✉❣❤t❡r

❝❡❧❧s t❡♥❞ t♦ ❛❝❝✉♠✉❧❛t❡ ❧♦❝❛❧❧② ②✐❡❧❞✐♥❣ ❞❡♥s❡ ❛♥❞ ❞✐s❝r❡t❡ ♠✐❝r♦❝♦❧♦♥✐❡s✳ ■♥ t❤❡

♦♣♣♦s✐t❡ ❢♦r s♠❛❧❧ ✈❛❧✉❡s ♦❢ β✱ ❜❛❝t❡r✐❛ ❛♥❞ t❤❡✐r ❞❛✉❣❤t❡r ❝❡❧❧s t❡♥❞ t♦ ❞✐s♣❡rs❡

❛♥❞ t❤❡ ②✐❡❧❞❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ❤❛✈❡ ❛♠♦r♣❤♦✉s s❤❛♣❡✳ ❆♥❛❧♦❣♦✉s❧②✱ s✐♠✉❧❛t✐♦♥ ✇✐t❤

❞✐✛❡r❡♥t ✈❛❧✉❡s ♦❢ t❤❡ ♣r♦❞✉❝t ❡①❝r❡t✐♦♥ r❛t✐♦ Yp ✭❊q✉❛t✐♦♥ ✺✳✼✮✱ ❛t ❛ ❝♦♥st❛♥t

✈❛❧✉❡ ♦❢ β✱ ❜❡t✇❡❡♥ t❤❡ t✇♦ ❡①tr❡♠❡ ❝❛s❡s ♦❢ Yp = 0 ✭♥♦ ♣r♦❞✉❝t ❡①❝r❡t✐♦♥✮ ❛♥❞

Yp = 1.0 ✭♥♦ ❣r♦✇t❤✱ ❛❧❧ t❤❡ s✉❜str❛t❡ ✐s r❡❧❡❛s❡❞ ❜❛❝❦ ♦♥ t❤❡ ❢♦r♠ ♦❢ ♣r♦❞✉❝t✮ ②✐❡❧❞s

♣❛tt❡r♥s t❤❛t ✈❛r② r❡s♣❡❝t✐✈❡❧② ❢r♦♠ ✉♥✐❢♦r♠ ❞✐str✐❜✉t✐♦♥ ♦❢ t❤❡ ❜❛❝t❡r✐❛ t♦ t❤❡

❢♦r♠❛t✐♦♥ ♦❢ ✐s♦❧❛t❡❞✱ r♦✉♥❞✲s❤❛♣❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ✭❞❛t❛ ♥♦t s❤♦✇♥✮✳ ❚❤✐s s✉❣❣❡sts

t❤❛t t❤❡ ❜✐♥❞✐♥❣ ❛✣♥✐t② ❢❛❝t♦r (β) ❛♥❞ t❤❡ ♣r♦❞✉❝t ❡①❝r❡t✐♦♥ r❛t❡ ♠❛② ❤❛✈❡ ❛

s✐❣♥✐✜❝❛♥t ✐♠♣❛❝t ♦♥ t❤❡ ♣❛tt❡r♥s ♦❢ s♣❛t✐❛❧ ❞✐str✐❜✉t✐♦♥ ♦❢ t❤❡ ❜❛❝t❡r✐❛✳ ■♥ ♦✉r

♠♦❞❡❧✱ t❤❡ s✉❜str❛t❡ ❝♦♥❝❡♥tr❛t✐♦♥ ✐♠♣❛❝ts t❤❡ r❛t❡ ♦❢ ♣r♦❞✉❝t ❡①❝r❡t✐♦♥✳ ❆♥ ✐♥✐t✐❛❧

❧♦✇ s✉❜str❛t❡ ❧❡✈❡❧ ②✐❡❧❞s ❧♦✇ r❛t❡s ♦❢ ♣r♦❞✉❝t ❡①❝r❡t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✇❤✐❝❤

♠❛② ♥♦t ❜❡ s✉✣❝✐❡♥t t♦ r❡❞✉❝❡ t❤❡ ♠♦t✐❧✐t② ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❛♥❞ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢

♠✐❝r♦❝♦❧♦♥✐❡s✳ ■♥ ♦✉r s✐♠✉❧❛t✐♦♥ t❤❡ ✐♥✐t✐❛❧ s✉❜str❛t❡ ❧❡✈❡❧ ✐s r❡❧❛t✐✈❡❧② ❤✐❣❤ ❛♥❞

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✼✽

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

✭❛✮ time = 9hours

✭❜✮ time = 18hours

❋✐❣✉r❡ ✺✳✹✿ ❖✈❡r❛❧❧ ❛♥❞ ③♦♦♠❡❞ ✈✐❡✇ ♦❢ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❢♦r♠❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛

✭❜❧❛❝❦ ❞♦ts✮ ❛♥❞ t❤❡ ❡①❝r❡t❡❞ ♠❛❝r♦♠♦❧❡❝✉❧❡s ✭❣r❛② s❝❛❧❡✮ ❢♦r ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✭β = 0✮

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✺✳✹✳ ❉✐s❝✉ss✐♦♥ ✼✾

♦♥❧② 90% ♦❢ t❤✐s ✐♥✐t✐❛❧ st♦❝❦ ✐s ❝♦♥s✉♠❡❞ ❜② t❤❡ ❡♥❞ ♦❢ t❤❡ s✐♠✉❧❛t✐♦♥✳

❲❡ ✐♥✈❡st✐❣❛t❡ ❤♦✇ t❤❡ ✐♥t❡r❝♦♥♥❡❝t✐♦♥s ❜❡t✇❡❡♥ t❤❡ ♠✐❝r♦❝♦❧♦♥✐❡s ❢♦r♠ ✐♥ t❤❡

❝❛s❡ ♦❢ ❧❛r❣❡ ✈❛❧✉❡ ♦❢ ❜✐♥❞✐♥❣ ❛✣♥✐t② ♣❛r❛♠❡t❡r (β = 500)✳ ❋✐❣✉r❡ ✺✳✽ s❤♦✇s ❛

③♦♦♠❡❞ ✈✐❡✇ ♦❢ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡ ✐♥t❡r❝♦♥♥❡❝t✐♦♥ ❜❡t✇❡❡♥ t✇♦ ♥❡✐❣❤❜♦r✐♥❣ ♠✐✲

❝r♦❝♦❧♦♥✐❡s✳

❚❤❡ ✐♥t❡r❝♦♥♥❡❝t✐♦♥ s❡❡♠s t♦ ❜❡ ❝r❡❛t❡❞ ❜② ❜❛❝t❡r✐❛ ✇❤✐❝❤ ❣♦ ❢r♦♠ ❛ ♠✐❝r♦❝♦❧♦♥②

t♦ ❛ ♥❡✐❣❤❜♦r✐♥❣ ♦♥❡✱ ❛♥❞ ✇❤✐❝❤ ♣r♦❣r❡ss✐✈❡❧② ❛❝❝✉♠✉❧❛t❡ ❡①❝r❡t❡❞ ♣r♦❞✉❝t ♦♥ t❤❡

♣❛t❤✳ ❚❤❡ r❡s✉❧t❛♥t ♣❛tt❡r♥ ✐s ❢♦r♠❡❞ ✇✐t❤ ❞❡♥s❡ ❛♥❞ ❞✐s❝r❡t❡ ♠✐❝r♦❝♦❧♦♥✐❡s ✐♥t❡r✲

❝♦♥♥❡❝t❡❞ ✇✐t❤ r❡❧❛t✐✈❡❧② t❤✐♥ str❛♥❞s ♦❢ ❜❛❝t❡r✐❛ ❛♥❞ ❡①❝r❡t❡❞ ♣r♦❞✉❝t✳

✺✳✹ ❉✐s❝✉ss✐♦♥

■♥ t❤✐s ✇♦r❦ ✇❡ ❛❜str❛❝t ❡①♣❡r✐♠❡♥t❛❧ ♦❜s❡r✈❛t✐♦♥s ♦♥ P✳ ❛❡r✉❣✐✲

♥♦s❛ ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t ❬❲❤✐t❝❤✉r❝❤ ✷✵✵✷❪ ❬❑❧❛✉s❡♥ ✵✵✸❛❪ ❬❑❧❛✉s❡♥ ✵✵✸❜❪

❬❆❧❧❡s❡♥✲❍♦❧♠ ✷✵✵✻❪❬❇❛r❦❡♥ ✷✵✵✽❪✐♥ ❛♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❛♥❞ ✐♥✈❡st✐❣❛t❡

❤♦✇ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② r❡❞✉❝t✐♦♥ ❞✉❡ t♦ ❛ s❡❧❢✲♣r♦❞✉❝❡❞ s✉❜st❛♥❝❡ ②✐❡❧❞s ❞✐✛❡r❡♥t

s♣❛t✐❛❧ ♣❛tt❡r♥s ❞✉r✐♥❣ t❤❡ ❡❛r❧② st❛❣❡s ♦❢ ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t✳ ❖✉r s✐♠✉❧❛t✐♦♥

r❡s✉❧ts s✉❣❣❡st t❤❛t s❡❧❢✲♣r♦❞✉❝❡❞ s✉❜st❛♥❝❡✲♠❡❞✐❛t❡❞ ♠♦t✐❧✐t② r❡❞✉❝t✐♦♥ ❞♦❡s ♣❧❛②

❛ r♦❧❡ ✐♥ ♠✐❝r♦❝♦❧♦♥② ❢♦r♠❛t✐♦♥✳ ❋✉rt❤❡r♠♦r❡✱ ✐♥ s♦♠❡ ❝❛s❡s✱ t❤❡s❡ s✐♠✉❧❛t❡❞

♠✐❝r♦❝♦❧♦♥✐❡s ❜✉✐❧❞ ✐♥t❡r❝♦♥♥❡❝t✐♦♥s✱ s✐♠✐❧❛r t♦ ✐♥t❡r❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s

♦❜s❡r✈❡❞ ❞✉r✐♥❣ t❤❡ ❡❛r❧② st❛❣❡s ♦❢ P✳ ❛❡r✉❣✐♥♦s❛ ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t ✐♥ ✢♦✇

❝❤❛♠❜❡rs❬❆❧❧❡s❡♥✲❍♦❧♠ ✷✵✵✻❪✱ ❛♥❞ ❛❧s♦ ✐♥ ❜✐♦✜❧♠s ❢♦r♠❡❞ ❜② Ps❡✉❞♦♠♦♥❛s s♣❡❝✐❡s

✐♥ ♠❛r✐♥❡ ❡♥✈✐r♦♥♠❡♥ts ❬❉❛❧t♦♥ ✶✾✾✹❪❬❉❛❧t♦♥ ✶✾✾✻❪✳

❙❡✈❡r❛❧ ❛✉t❤♦rs ❛❧r❡❛❞② ❡①♣❧♦r❡❞ t❤❡ ♠❡❝❤❛♥✐s♠s ②✐❡❧❞✐♥❣ ♠✐❝r♦❝♦❧♦♥✐❡s ✐♥

❜✐♦✜❧♠s❬❆❧♣❦✈✐st ✷✵✵✻❪❬P✐❝✐♦r❡❛♥✉ ✷✵✵✼❪✳ ❍♦✇❡✈❡r✱ t❤❡ ♣❛tt❡r♥ ♦❢ ✐♥t❡r❝♦♥♥❡❝t❡❞

♠✐❝r♦❝♦❧♦♥✐❡s ❝❛♥♥♦t ❜❡ ♦❜t❛✐♥❡❞ ✇✐t❤ t❤❡s❡ ✉s✉❛❧ ♠❡❝❤❛♥✐s♠s✿ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛

❢♦r♠ ✐s♦❧❛t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ❛♥❞ ❝♦♥st❛♥t❧② ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ❢♦r♠ ✢❛t ❜✐♦✜❧♠s✳ ❇❛s❡❞

♦♥ ❡①♣❡r✐♠❡♥t❛❧ ❞❛t❛ ❛♥❞ ❝♦♠♣✉t❡r s✐♠✉❧❛t✐♦♥s ✇❡ s✉❣❣❡st ❛ ♠❡❝❤❛♥✐s♠ t❤❛t ❝♦✉❧❞

❜❡ r❡s♣♦♥s✐❜❧❡ ❢♦r t❤❡ ♦❜s❡r✈❡❞ ♣❛tt❡r♥s✳ ❖✉r ♠♦❞❡❧ s❤♦✇s t❤❛t ♠✐❝r♦❝♦❧♦♥✐❡s ♠❛②

r❡s✉❧t ❢r♦♠ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② r❡❞✉❝t✐♦♥ ❜② s❡❧❢✲♣r♦❞✉❝❡❞ ♠❛❝r♦♠♦❧❡❝✉❧❡s✳ ❚❤❡ ❛♥❛❧✲

②s✐s ♦❢ t❤❡ s✐♠✉❧❛t✐♦♥ r❡s✉❧ts s✉❣❣❡sts t❤❛t ❝❡❧❧s ♦♥ t❤❡ ❡❞❣❡ ♦❢ ❛ ♠✐❝r♦❝♦❧♦♥② ♦❝❝❛✲

s✐♦♥❛❧❧② ❞❡t❛❝❤ ❛♥❞ ✉♥❞❡r❣♦ ❛ s✉r❢❛❝❡✲❛ss♦❝✐❛t❡❞ ♠♦t✐❧✐t② ✉♥t✐❧ ❜❡✐♥❣ ❝❛♣t✉r❡❞ ❜② ❛

♥❡✐❣❤❜♦r✐♥❣ ♠✐❝r♦❝♦❧♦♥②✳ ❚❤❡ ♣❛t❤ ♦❢ t❤❡ ♠✐❣r❛t✐♥❣ ❝❡❧❧ ✐s ♠❛r❦❡❞ ❜② t❤❡ ❡①❝r❡t❡❞

♠❛❝r♦♠♦❧❡❝✉❧❡s ❛♥❞ ✐s ♣r♦❣r❡ss✐✈❡❧② r❡✐♥❢♦r❝❡❞ ❜② ♦t❤❡r ♠✐❣r❛t✐♥❣ ❝❡❧❧s✳ ❚❤✐s r❡✲

s✉❧ts ✐♥ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❛♥ ✐♥t❡r❝♦♥♥❡❝t✐♦♥ ❜❡t✇❡❡♥ t❤❡ ♥❡✐❣❤❜♦r✐♥❣ ♠✐❝r♦❝♦❧♦♥✐❡s✳

❍♦✇❡✈❡r✱ ♠♦r❡ ✐♥✈❡st✐❣❛t✐♦♥ ✐s ♥❡❝❡ss❛r② t♦ str❡♥❣t❤❡♥ ♦r ❢❛❧s✐❢② t❤✐s ❤②♣♦t❤❡s✐s✳

❚❤✐s ✐♥✈❡st✐❣❛t✐♦♥ ❝♦✉❧❞ ❜❡ ✐♠♣♦rt❛♥t ❢♦r ❛ ❜❡tt❡r ✉♥❞❡rst❛♥❞✐♥❣ ♦❢ ❜✐♦✜❧♠ ❢✉♥❝✲

t✐♦♥s✳ ■♥❞❡❡❞✱ ✐t ✐s ✇❡❧❧ ❛❝❝❡♣t❡❞ t❤❛t t❤❡ ♣r❡s❡♥❝❡ ♦❢ ❞✐✛❡r❡♥t s✉❜♣♦♣✉❧❛t✐♦♥s ✐♥

♠✐❝r♦❝♦❧♦♥✐❡s ❝❛♥ ❢❛✈♦r t❤❡ s✉r✈✐✈❛❧ ♦❢ ♦♥❡ ♦r ♠♦r❡ s✉❜♣♦♣✉❧❛t✐♦♥s ✉♥❞❡r ❛❞✈❡rs❡

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✽✵

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

✭❛✮ time = 9hours

✭❜✮ time = 18hours

❋✐❣✉r❡ ✺✳✺✿ ❖✈❡r❛❧❧ ❛♥❞ ③♦♦♠❡❞ ✈✐❡✇ ♦❢ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❢♦r♠❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛

✭❜❧❛❝❦ ❞♦ts✮ ❛♥❞ t❤❡ ❡①❝r❡t❡❞ ♠❛❝r♦♠♦❧❡❝✉❧❡s ✭❣r❛② s❝❛❧❡✮ ❢♦r ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛

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✺✳✹✳ ❉✐s❝✉ss✐♦♥ ✽✶

✭❛✮ time = 9hours

✭❜✮ time = 18hours

❋✐❣✉r❡ ✺✳✻✿ ❖✈❡r❛❧❧ ❛♥❞ ③♦♦♠❡❞ ✈✐❡✇ ♦❢ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❢♦r♠❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛

✭❜❧❛❝❦ ❞♦ts✮ ❛♥❞ t❤❡ ❡①❝r❡t❡❞ ♠❛❝r♦♠♦❧❡❝✉❧❡s ✭❣r❛② s❝❛❧❡✮ ❢♦r ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✭β =

100✮

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✽✷

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

✭❛✮ time = 9hours

✭❜✮ time = 18hours

❋✐❣✉r❡ ✺✳✼✿ ❖✈❡r❛❧❧ ❛♥❞ ③♦♦♠❡❞ ✈✐❡✇ ♦❢ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ❢♦r♠❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛

✭❜❧❛❝❦ ❞♦ts✮ ❛♥❞ t❤❡ ❡①❝r❡t❡❞ ♠❛❝r♦♠♦❧❡❝✉❧❡s ✭❣r❛② s❝❛❧❡✮ ❢♦r ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✭β =

500✮

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✺✳✹✳ ❉✐s❝✉ss✐♦♥ ✽✸

✭❛✮ time = 9hours

✭❜✮ time = 18hours

❋✐❣✉r❡ ✺✳✽✿ ❩♦♦♠❡❞ ✈✐❡✇ ♦❢ ✐♥t❡r❝♦♥♥❡❝t✐♦♥ ❢♦r♠❛t✐♦♥ ❜❡t✇❡❡♥ t✇♦ ♠✐❝r♦❝♦❧♦♥✐❡s

❢♦r ❛ ❜✐♥❞✐♥❣ ❛✣♥✐t② β = 500✳ ❇❛❝t❡r✐❛ ❛r❡ r❡♣r❡s❡♥t❡❞ ✇✐t❤ ❣r❡❡♥ ❞♦ts ❛♥❞ t❤❡

❡①❝r❡t❡❞ ♣r♦❞✉❝t ❝♦♥❝❡♥tr❛t✐♦♥ ✇✐t❤ ❣r❛② s❝❛❧❡✳

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✽✹

❈❤❛♣t❡r ✺✳ ❆ ❞❡t❛✐❧❡❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

❝♦♥❞✐t✐♦♥s ❬P❛rs❡❦ ✷✵✵✽❪❬❏♦❤♥s♦♥ ✷✵✵✽❪✳ ❍♦✇❡✈❡r✱ r❡❝❡♥t ♦❜s❡r✈❛t✐♦♥s s✉❣❣❡st t❤❛t

✐♥ s♦♠❡ ❝❛s❡s t❤❡ ♠❛tr✐① ♦❢ ❡①tr❛❝❡❧❧✉❧❛r ❉◆❆ ✭❛♥❞ ♣♦ss✐❜❧② ♦t❤❡r ♣r♦❞✉❝ts✮ ♠❛②

❣✉✐❞❡ ♠✐❣r❛t✐♦♥ ♦❢ t❤❡ ❝❡❧❧s ❜❡t✇❡❡♥ ♠✐❝r♦❝♦❧♦♥✐❡s ❬▲✉ ✷✵✵✺❪❬❇❛r❦❡♥ ✷✵✵✽❪ ❢❛✈♦r✐♥❣ ❛

t②♣❡ ♦❢ ❝♦❧❧❛❜♦r❛t✐♦♥ ❜❡t✇❡❡♥ ❞✐st✐♥❝t s✉❜♣♦♣✉❧❛t✐♦♥s ✇✐t❤✐♥ ❛ ❜✐♦✜❧♠✳ ❚❤✐s ♠❛② ❜❡

r❡❧❛t❡❞ t♦ st✉❞✐❡s ✐♥ ❧❛♥❞s❝❛♣❡ ❡❝♦❧♦❣② ✇❤❡r❡ t❤✐s ♣❛tt❡r♥ ♦❢ ✐♥t❡r❝♦♥♥❡❝t❡❞ ❤❛❜✐t❛ts

✐s r❡❝♦❣♥✐③❡❞ ❛s ♣❛rt✐❝✉❧❛r❧② ✐♠♣♦rt❛♥t ✭❇✉r❡❧ ❛♥❞ ❇❛✉❞r②✱ ✷✵✵✸✮ ❬❇✉r❡❧ ✷✵✵✸❪✳

■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧s ❛r❡ ❛♣♣❡❛❧✐♥❣ t♦ ♠✐❝r♦❜✐♦❧♦❣✐sts ❜❡❝❛✉s❡ ♦❢ t❤❡ ❡♠♣❤❛s✐s

♦♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧ ❛s t❤❡ ❢✉♥❞❛♠❡♥t❛❧ ✉♥✐t ❛♥❞ t❤❡ r✐❝❤♥❡ss ♦❢ t❤❡✐r ❞②♥❛♠✐❝✳

❍♦✇❡✈❡r ✇❤❡♥ t❤❡② ❛r❡ t♦♦ ❝♦♠♣❧❡① t❤❡② ♦❢t❡♥ ❜❡❝♦♠❡ ❞✐✣❝✉❧t t♦ ❛♥❛❧②③❡ ✇❤✐❝❤

❧✐♠✐ts t❤❡✐r ♣r❛❝t✐❝❛❧ ♣❛②♦✛ ❬●r✐♠♠ ✷✵✵✺❪✳ ❚❤❡r❡❢♦r❡✱ ✇❡ ❤❛✈❡ ❛tt❡♠♣t❡❞ t♦ ❦❡❡♣

♦✉r ♠♦❞❡❧ ❛s s✐♠♣❧❡ ❛s ♣♦ss✐❜❧❡ ❛♥❞ ✐♥s♣✐r❡❞ ❜② t❤❡ ♣❤❡♥♦♠❡♥♦❧♦❣✐❝❛❧ r❡s✉❧ts ♠❡♥✲

t✐♦♥❡❞ ✐♥ t❤❡ ✐♥tr♦❞✉❝t✐♦♥✱ ❜✉t r✐❝❤ ❡♥♦✉❣❤ t♦ ♣r♦❞✉❝❡ ♣❛tt❡r♥s ♦❢ ✐♥t❡r❝♦♥♥❡❝t❡❞

♠✐❝r♦❝♦❧♦♥✐❡s✳ ❏♦❤♥s♦♥ ❬❏♦❤♥s♦♥ ✷✵✵✽❪ ♣r♦♣♦s❡❞ ❛ ♠♦❞❡❧ ❜❛s❡❞ ♦♥ t❤❡ ❛ss✉♠♣t✐♦♥

♦❢ t❤❡ ✑❞✐r❡❝t✑ ✐♥t❡r❛❝t✐♦♥ ❜❡t✇❡❡♥ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s t❤r♦✉❣❤ ❛ttr❛❝t✐✈❡ ✭❛♥❞ r❡♣✉❧✲

s✐✈❡✮ ❢♦r❝❡s ❛r❣✉✐♥❣ t❤❛t ❢♦r❝❡s ❜❡t✇❡❡♥ ❝❡❧❧s ❝❛♥ ❜❡ ❛ ♣r♦①② ❢♦r t❤❡ ❜❡❤❛✈✐♦r ✇❡

❡①♣❡❝t t♦ s❡❡ ❞✉❡ t♦ ❝❤❡♠♦t❛①✐s ✐♥ r❡s♣♦♥s❡ t♦ ❝❤❡♠✐❝❛❧s r❡❧❡❛s❡❞ ❜② ♦t❤❡r ❝❡❧❧s

❬❏♦❤♥s♦♥ ✷✵✵✽❪✳ ❚❤❡ ❛ss✉♠♣t✐♦♥ s✐♠♣❧✐✜❡s t❤❡ ♠♦❞❡❧ ❛s t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ❡①✲

❝r❡t❡❞ ♣r♦❞✉❝t ✐s ♥♦t ❝♦♥s✐❞❡r❡❞ ❡①♣❧✐❝✐t❧②✳ ❚❤✐s ✐s ❛ r❡❛s♦♥❛❜❧❡ ❛ss✉♠♣t✐♦♥ ✇❤❡♥

t❤❡ ❞②♥❛♠✐❝s ♦❢ t❤❡ ❝❤❡♠✐❝❛❧ ❜❡✐♥❣ ♣r♦❞✉❝❡❞ ✐s ❢❛st ✭❤✐❣❤ ❞✐✛✉s✐♦♥✮ ❝♦♠♣❛r❡❞ t♦ t❤❡

❞②♥❛♠✐❝ ♦❢ t❤❡ ❜❛❝t❡r✐❛ ✭♠♦t✐❧✐t② ❛♥❞ ❣r♦✇t❤✮ ❬▲❡❡ ✷✵✵✶❪✳ ❖✉r ♠♦❞❡❧ ✐s ❜❛s❡❞ ♦♥

t❤❡ ❛ss✉♠♣t✐♦♥ t❤❛t t❤❡ ❡①❝r❡t❡❞ ♠❛❝r♦♠♦❧❡❝✉❧❡s ❧✐❦❡ ❉◆❆ ❛♥❞ ❡①♦♣♦❧②♠❡rs ❞✐✛✉s❡

❛t ❧♦✇ r❛t❡s ❛♥❞ ♣❡rs✐st ♦♥ t❤❡ ♣❛t❤ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛✳ ❚❤✐s s❡❡♠s t♦ ♣❧❛② ❛

r♦❧❡ ✐♥ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡ ✐♥t❡r❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ❛s ♠✐❝r♦❝♦❧♦♥✐❡s ②✐❡❧❞❡❞ ❜②

❏♦❤♥s♦♥✬s ♠♦❞❡❧ t❤r♦✉❣❤ ❛ttr❛❝t✐✈❡✴r❡♣✉❧s✐✈❡ ❢♦r❝❡s s❡❡♠ ♥♦t t♦ ❜❡ ✐♥t❡r❝♦♥♥❡❝t❡❞

❬❏♦❤♥s♦♥ ✷✵✵✽❪✳ ❖✉r st✉❞② ✐♥❝❧✉❞❡❞✱ ❤♦✇❡✈❡r✱ s♦♠❡ ❧✐♠✐t❛t✐♦♥s t❤❛t s❤♦✉❧❞ ❜❡ ❛❝✲

❦♥♦✇❧❡❞❣❡❞ ❢♦r ❢✉t✉r❡ r❡s❡❛r❝❤ ✐♥ t❤✐s ❛r❡❛✳ ❊①❛♠♣❧❡s✱ ✐♥❤❡r❡♥t t♦ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧✐♥❣ ❛♣♣r♦❛❝❤✱ ✐♥❝❧✉❞❡ t❤❡ q✉❡st✐♦♥ ♦❢ ❤♦✇ t♦ ♠❡❛s✉r❡ t❤❡ ✑❣♦♦❞♥❡ss✑ ♦❢ ❛♥

■❇▼✳ ●r✐♠♠ ❛♥❞ ❘❛✐❧s❜❛❝❦ ❬●r✐♠♠ ✷✵✵✺❪ s✉❣❣❡st❡❞ t❤❛t t❡st✐♥❣ ❛♥ ■❇▼ ❛❣❛✐♥st

♠✉❧t✐♣❧❡ ♦❜s❡r✈❡❞ ♣❛tt❡r♥s ✐s ❛ ♣♦✇❡r❢✉❧ ✇❛② t♦ ❛ss❡ss t❤❡ ■❇▼ ❝❛♣❛❝✐t② t♦ ❝❛♣t✉r❡

s②st❡♠✬s ❡ss❡♥t✐❛❧ ❝❤❛r❛❝t❡r✐st✐❝s✳ ■♥ t❤✐s ✇♦r❦ ✇❡ ❛ss❡ss❡❞ t❤❡ ✑❣♦♦❞♥❡ss✑ ♦❢ ♦✉r

■❇▼ t❤r♦✉❣❤ ❝♦♠♣❛r✐s♦♥ ♦❢ ❛♥ ♦❜s❡r✈❡❞ ♣❛tt❡r♥ ✭❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ✐♥ ✜❣✳✶✮

t♦ ❛ s✐♠✉❧❛t❡❞ ♦♥❡ ✭✜❣✳✽✮✳ ❉❡s♣✐t❡ t❤❡ s✐♠✐❧❛r✐t✐❡s ❜❡t✇❡❡♥ t❤❡ ❡①♣❡r✐♠❡♥t❛❧ ❛♥❞

s✐♠✉❧❛t❡❞ ♣❛tt❡r♥s ✭t❤✐♥ ♣❛t❤ ♦❢ ❜❛❝t❡r✐❛ ❛♥❞ ♣r♦❞✉❝t ❝♦♥♥❡❝t✐♥❣ ♥❡✐❣❤❜♦r✐♥❣ ♠✐✲

❝r♦❝♦❧♦♥✐❡s✮ t❤❡r❡ ❛r❡ st✐❧❧ ❞✐✛❡r❡♥❝❡s✳ ❋♦r ❡①❛♠♣❧❡ ❝❡❧❧s s✉rr♦✉♥❞❡❞ t❤❡ t❤✐♥ ♣❛t❤ ✐♥

✜❣✉r❡ ✶ ✇❤✐❧❡ t❤❡② ❛r❡ ❝♦♥t❛✐♥❡❞ ✐♥ t❤❡ ❛r❡❛ ✇✐t❤ ❤✐❣❤ ❛♠♦✉♥t ♦❢ ♣r♦❞✉❝t ✐♥ ✜❣✉r❡ ✽✳

❚❤❡r❡❢♦r❡✱ ❛❞❞✐t✐♦♥❛❧ ♣❛tt❡r♥s s❤♦✉❧❞ ❜❡ ✐❞❡♥t✐✜❡❞ ❛♥❞ ❝♦♠♣❛r❡❞ t♦ t❤❡ s✐♠✉❧❛t❡❞

♦♥❡s ✐♥ ♦r❞❡r t♦ str❡♥❣t❤❡♥ ♦r ❢❛❧s✐❢② t❤❡ ❤②♣♦t❤❡t✐❝❛❧ ✐♠♣❧✐❝❛t✐♦♥ ♦❢ s❡❧❢✲❡①❝r❡t❡❞

♣r♦❞✉❝t ✐♥ ♠♦t✐❧✐t② r❡❞✉❝t✐♦♥ ❛♥❞ ❢♦r♠❛t✐♦♥ ♦❢ ✐♥t❡r❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s✳ ❆♥✲

♦t❤❡r ❧✐♠✐t❛t✐♦♥ ♦❢ ♦✉r ♠♦❞❡❧ ✐s t❤❡ ❞❡t❡r♠✐♥❛t✐♦♥ ♦❢ ♣❛r❛♠❡t❡rs ❧✐❦❡ t❤❡ ❜✐♥❞✐♥❣

❛✣♥✐t② ❢❛❝t♦r (β) ❛♥❞ ❝❡❧❧ ❞✐✛✉s✐♦♥ (Df )✳ ❚❤❡s❡ ♣❛r❛♠❡t❡rs ♠❛② ❜❡ ❞✐✣❝✉❧t t♦

♦❜t❛✐♥ ❢r♦♠ ❡①♣❡r✐♠❡♥t❛❧ ♦❜s❡r✈❛t✐♦♥s ❛♥❞ t❤❡✐r ✐♠♣❛❝t s❤♦✉❧❞ ❜❡ ❛ss❡ss❡❞ t❤r♦✉❣❤

s❡♥s✐t✐✈✐t② ❛♥❛❧②s✐s✳

Page 98: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✺✳✹✳ ❉✐s❝✉ss✐♦♥ ✽✺

❋✐♥❛❧❧②✱ t❤❡ ♠♦❞❡❧ ❝❛♥ ❜❡ ❡①t❡♥❞❡❞ t♦ ✐♥✈❡st✐❣❛t❡ t❤❡ ❡✛❡❝t ♦❢ ♦t❤❡r ♠❛❝r♦✲

♠♦❧❡❝✉❧❡s ❧✐❦❡ ❡①♦♣♦❧②♠❡rs ♦♥ t❤❡ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② ❛♥❞ ♠✐❝r♦❝♦❧♦♥✐❡s ❢♦r♠❛t✐♦♥✳

❆♥♦t❤❡r ♣♦t❡♥t✐❛❧ ❡①t❡♥s✐♦♥ ✐s t♦ ✐♥❝❧✉❞❡ ❛❞❞✐t✐♦♥❛❧ ♣r♦❝❡ss❡s ❧✐❦❡ ❜❛❝t❡r✐❛ ❞❡t❛❝❤✲

♠❡♥t ❛♥❞ s✉❜str❛t❡ ❢❡❡❞✐♥❣ ✇❤✐❝❤ ❛❧❧♦✇ ✐♥✈❡st✐❣❛t✐♥❣ t❤❡ ❡✛❡❝t ♦❢ t❤❡ ✐♥t❡r❛❝t✐♦♥s

❜❡t✇❡❡♥ ❝❡❧❧ ♠♦t✐❧✐t② ❛♥❞ ❡①❝r❡t❡❞ ♠❛❝r♦♠♦❧❡❝✉❧❡s ♦♥ t❤❡ ❛r❝❤✐t❡❝t✉r❡ ♦❢ ♠❛t✉r❡

❜✐♦✜❧♠s✳

Page 99: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and
Page 100: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❈❤❛♣t❡r ✻

▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ ❛♥

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❛

❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡

❜❛❝t❡r✐❛

❈♦♥t❡♥ts

✻✳✶ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✽

✻✳✶✳✶ ❖✈❡r✈✐❡✇ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✽✽

✻✳✶✳✷ ❉❡t❛✐❧s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✵

✻✳✷ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✷

✻✳✷✳✶ ❋✐rst ♠♦♠❡♥t ❞②♥❛♠✐❝s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✷

✻✳✷✳✷ ❙❡❝♦♥❞ ♠♦♠❡♥t ❞②♥❛♠✐❝s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✾✸

✻✳✷✳✸ ❈❧♦s✉r❡ ♦❢ t❤❡ ♠♦♠❡♥t ❤✐❡r❛r❝❤② ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✵

✻✳✷✳✹ ❙♦❧✈✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✵

✻✳✸ ❘❡s✉❧ts ❛♥❞ ❞✐s❝✉ss✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✵✵

✻✳✹ ❈♦♥❝❧✉s✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✶

■♥ t❤✐s ❝❤❛♣t❡r ✇❡ ❞❡r✐✈❡ ❛ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧ ✭■❇▼✮ ❞❡s❝r✐❜✐♥❣ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ♠✐❝r♦❝♦❧♦♥✐❡s ❞✉❡ t♦ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t②

r❡❞✉❝t✐♦♥ ❜② ❛ s❡❧❢✲♣r♦❞✉❝❡❞ ♣r♦❞✉❝t✳ ❚❤❡ ❞✐r❡❝t ❞❡r✐✈❛t✐♦♥ ♦❢ ♠♦♠❡♥t ♠♦❞❡❧s ♦❢

t❤❡ ■❇▼ ♣r❡s❡♥t❡❞ ✐♥ ❝❤❛♣t❡r ✺ ✐s ❞✐✣❝✉❧t✳ t❤✉s ✇❡ st❛rt ❜② s✐♠♣❧✐❢②✐♥❣ t❤❡ ■❇▼ t❤❛♥

❛♣♣r♦①✐♠❛t✐♥❣ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✇✐t❤ ❛ ♠♦♠❡♥t ♠♦❞❡❧✳ ❚❤❡ ♠❛✐♥ s✐♠♣❧✐✜❝❛t✐♦♥s

❝♦♥s✐st ✐♥ r❡♣r❡s❡♥t✐♥❣ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✭❜❛❝t❡r✐❛ ❛♥❞ ♣r♦❞✉❝t✮ ❛s ♣♦✐♥t ♣❛rt✐❝❧❡s✳

❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛❣❣r❡❣❛t❡s t❤❡ st❛t❡ ✈❛r✐❛❜❧❡s ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✐♥t♦ t✇♦

t②♣❡ ♦❢ q✉❛♥t✐t✐❡s✿ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✭❜❛❝t❡r✐❛ ❛♥❞ ♣♦❧②♠❡r✮ ✇❤✐❝❤

❝♦rr❡s♣♦♥❞ t♦ t❤❡ ✜rst s♣❛t✐❛❧ ♠♦♠❡♥t ❛♥❞ t❤❡ ❛✈❡r❛❣❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ ❛♥ ✐♥❞✐✈✐❞✲

✉❛❧ ❛t ❞✐✛❡r❡♥t ❞✐st❛♥❝❡s✱ ♠❡❛s✉r❡❞ ❜② t❤❡ s❡❧❢ ❛♥❞ ❝r♦ss ♣❛✐r ❞❡♥s✐t② ❝♦rr❡❧❛t✐♦♥

❢✉♥❝t✐♦♥s ✭s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥ts✮✳ ❚❤❡ ✢✉❝t✉❛t✐♦♥ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ✐♥❞✐✲

✈✐❞✉❛❧s ♦❜s❡r✈❡❞ ✐♥ t❤❡ ■❇▼ ❛r❡ ❛✈❡r❛❣❡❞ ✐♥ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❲❡ s❤♦✇ ✐♥ t❤✐s

❝❤❛♣t❡r t❤❛t ✐❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ r❡s♣♦♥s❡ t♦ t❤❡s❡ ✢✉❝t✉❛t✐♦♥s ✐s ♥♦♥✲❧✐♥❡❛r ♦r ❞❡♣❡♥❞s

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✽✽ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

♦♥ ❛ t❤r❡s❤♦❧❞ ✈❛❧✉❡ t❤❛♥ ♠♦♠❡♥t ♠♦❞❡❧s ♠❛② ❢❛✐❧ ✐♥ ❝❛♣t✉r✐♥❣ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡

■❇▼✳

❚❤❡ ❝❤❛♣t❡r ✐s ♦r❣❛♥✐③❡❞ ✐♥ ❢♦✉r s❡❝t✐♦♥s✿ ✜rst ✇❡ st❛rt ❜② s✐♠♣❧✐❢②✐♥❣ t❤❡ ■❇▼

♣r❡s❡♥t❡❞ ✐♥ t❤❡ ♣r❡✈✐♦✉s ❝❤❛♣t❡r✳ ❚❤❛♥ ✇❡ ❞❡r✐✈❡ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧

♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✐♥ t❤❡ s❡❝♦♥❞ s❡❝t✐♦♥✳ ■♥ t❤❡ t❤✐r❞ s❡❝t✐♦♥ ✇❡ ❝♦♠♣❛r❡ t❤❡

♠♦♠❡♥t ❛♥❞ s✐♠♣❧✐✜❡❞ ■❇▼ s✐♠✉❧❛t✐♦♥s ❛♥❞ ✇❡ ❞✐s❝✉ss t❤❡ ❧✐♠✐ts ♦❢ t❤❡ ♠♦♠❡♥t

❛♣♣r♦❛❝❤ ✐♥ ❝♦♣✐♥❣ ✇✐t❤ t❤❡ ✢✉❝t✉❛t✐♦♥ ♦❢ t❤❡ ❧♦❝❛❧ ❡♥✈✐r♦♥♠❡♥t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳

✻✳✶ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼

✻✳✶✳✶ ❖✈❡r✈✐❡✇

✻✳✶✳✶✳✶ P✉r♣♦s❡

❚❤❡ ❛✐♠ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✐s t♦ ✐♥✈❡st✐❣❛t❡ t❤❡ ♣❛tt❡r♥s t❤❛t ❛r✐s❡

❢♦r♠❡❞ ❜② t❤❡ ❛❣❣r❡❣❛t✐♦♥ ♦❢ ✐♥❞✐✈✐❞✉❛❧ ♠♦t✐❧❡ ❝❡❧❧s ✐♥t♦ ♠✐❝r♦❝♦❧♦♥✐❡s ✇❤❡♥ t❤❡✐r

♠♦t✐❧✐t② ✐♥ r❡❞✉❝❡❞ ❜② ❛ s❡❧❢✲❡①❝r❡t❡❞ ♣♦❧②♠❡r✳

✻✳✶✳✶✳✷ ❙t❛t❡ ✈❛r✐❛❜❧❡s

❚❤❡ s②st❡♠ ❝♦♥t❛✐♥s t✇♦ t②♣❡s ♦❢ ❞✐s❝r❡t❡ ✐♥❞✐✈✐❞✉❛❧s✿ ❜❛❝t❡r✐❛❧ ❝❡❧❧s ❛♥❞ ♣♦❧②♠❡r✐❝

♣❛rt✐❝❧❡s✳ ❊❛❝❤ ✐♥❞✐✈✐❞✉❛❧ ✭❜❛❝t❡r✐✉♠ ♦r ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡✮ ✐s ❝❤❛r❛❝t❡r✐③❡❞ ❜② ❛

❝♦♥t✐♥✉♦✉s ♣♦s✐t✐♦♥ ✐♥ t❤❡ t✇♦✲❞✐♠❡♥s✐♦♥❛❧ ❞♦♠❛✐♥✳

✻✳✶✳✶✳✸ ❖✈❡r✈✐❡✇

❲❡ ❝♦♥s✐❞❡r ❛ ♣♦♣✉❧❛t✐♦♥ ♦❢ ❞✐s❝r❡t❡✱ ✐❞❡♥t✐❝❛❧ ✐♥❞✐✈✐❞✉❛❧ ❜❛❝t❡r✐❛❧ ❝❡❧❧s ✐♥❤❛❜✐t✐♥❣

❛ t✇♦ ❞✐♠❡♥s✐♦♥❛❧ ❝♦♥t✐♥✉♦✉s ❡♥✈✐r♦♥♠❡♥t✳ ❚❤❡ ❜❛❝t❡r✐❛ ✉♥❞❡r❣♦ ❢♦✉r st♦❝❤❛st✐❝

♣r♦❝❡ss❡s✿ t❤❡② ♠♦✈❡ ❛r♦✉♥❞ t❤❡ s♣❛t✐❛❧ ❞♦♠❛✐♥✱ ❡①❝r❡t❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s✱ ❞✐✈✐❞❡

✐♥t♦ t✇♦ ✐❞❡♥t✐❝❛❧ ❝❡❧❧s ❛♥❞ ❣❡t ❞❡t❛❝❤❡❞ ❢r♦♠ t❤❡ ❞♦♠❛✐♥✳ ❚❤❡ s♣❛t✐❛❧ ❞♦♠❛✐♥ ✐s

✐♥✐t✐❛❧❧② ❤♦♠♦❣❡♥❡♦✉s ❜✉t t❤❡ ♣r♦❣r❡ss✐✈❡ ❛❝❝✉♠✉❧❛t✐♦♥ ♦❢ t❤❡ ❡①❝r❡t❡❞ ♣♦❧②♠❡r✐❝

♣❛rt✐❝❧❡s ✐♥tr♦❞✉❝❡s s♣❛t✐❛❧ ❤❡t❡r♦❣❡♥❡✐t② t❤❛t ❛✛❡❝t t❤❡ ❞❡t❛❝❤♠❡♥t ❛♥❞ ♠♦t✐❧✐t②

r❛t❡s ♦❢ t❤❡ ❜❛❝t❡r✐❛✳ ❖✉r ♠❛✐♥ ❛ss✉♠♣t✐♦♥ ✐s t❤❛t t❤❡ ❛❝❝✉♠✉❧❛t✐♦♥ ♦❢ ♣♦❧②♠❡r✐❝

♣❛rt✐❝❧❡s r❡❞✉❝❡s t❤❡ ♠♦t✐❧✐t② ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❜✉t ✐♥❝r❡❛s❡s t❤❡✐r ♣r♦❜❛❜✐❧✐t② ♦❢ ❜❡✐♥❣

❞❡t❛❝❤❡❞✳ ❚❤✐s ✐s ❛ s✐♠♣❧✐✜❡❞ ❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ t❡♥❞❡♥❝② ♦❢ s♦♠❡ ❜❛❝t❡r✐❛ ❝♦❧♦♥✐③✐♥❣

❛ s✉r❢❛❝❡ t♦ ❡①❝r❡t❡ ❡①tr❛❝❡❧❧✉❧❛r ♣♦❧②♠❡r✐❝ s✉❜st❛♥❝❡s t❤❛t ❤♦❧❞ t❤❡ ❝❡❧❧s t♦❣❡t❤❡r

❛♥❞ ❛tt❛❝❤ t❤❡♠ t♦ t❤❡ s✉r❢❛❝❡✳ ❇✉t ✇❤❡♥ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ✐♥❝r❡❛s❡s✱

t❤❡ ♠✐❝r♦❝♦❧♦♥② ❣r♦✇s ✐♥ t❤❡ ✈❡rt✐❝❛❧ ❞✐♠❡♥s✐♦♥ ❛♥❞ ✐ts str✉❝t✉r❡ ✐s ✇❡❛❦❡♥❡❞ ❜②

t❤❡ ❤②❞r♦❞②♥❛♠✐❝ str❡ss❡s✳ ❋✐♥❛❧❧② ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ❝❛♥

❛❧s♦ ❞❡t❛❝❤ ❢r♦♠ t❤❡ s②st❡♠ ❛♥❞ t❤❛t t❤❡✐r ❞❡t❛❝❤♠❡♥t r❛t❡ ❛❧s♦ ✐♥❝r❡❛s❡s ✇✐t❤ t❤❡

✐♥❝r❡❛s❡ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡rs✳

✻✳✶✳✶✳✹ ❙❝❤❡❞✉❧✐♥❣

❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ■❇▼ ✐s ❣♦✈❡r♥❡❞ ❜② t❤❡ ❢♦❧❧♦✇✐♥❣ ❡✈❡♥ts✿

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✻✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✽✾

• ❉✐✈✐s✐♦♥ ♦❢ ❛ ❜❛❝t❡r✐❛❧ ❝❡❧❧

• Pr♦❞✉❝t✐♦♥ ♦❢ ❛ ♣♦❧②♠❡r ♣❛rt✐❝❧❡

• ❉❡t❛❝❤♠❡♥t ♦❢ ❜❛❝t❡r✐❛❧ ❝❡❧❧

• ❉❡t❛❝❤♠❡♥t ♦❢ ❛ ♣♦❧②♠❡r ♣❛rt✐❝❧❡

• ▼♦t✐❧✐t② ♦❢ ❛ ❜❛❝t❡r✐❛❧ ❝❡❧❧

❲❡ ✐♠♣❧❡♠❡♥t❡❞ t❤❡ ■❇▼ ✐♥ t❤❡ ❝♦♥t✐♥✉♦✉s t✐♠❡✳ ❚♦ s✐♠✉❧❛t❡ t❤❡ t❡♠♣♦r❛❧

❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ s②st❡♠ ✇❡ ♥❡❡❞ t♦ s♣❡❝✐❢② ✇❤❡♥ t❤❡ ♥❡①t ❡✈❡♥t ✇✐❧❧ ♦❝❝✉r✱ ✇❤❛t

❦✐♥❞ ♦❢ ❡✈❡♥t ✐t ✇✐❧❧ ❜❡ ❛♥❞ ✇❤✐❝❤ ✐♥❞✐✈✐❞✉❛❧ ✇✐❧❧ ❜❡ ❝♦♥❝❡r♥❡❞ ✇✐t❤ t❤❡ ❡✈❡♥t✳ ❲❡ ✉s❡

❛ ♣r♦❝❡❞✉r❡ ❛❞❛♣t❡❞ ❢r♦♠ t❤❡ ❛❧❣♦r✐t❤♠ ♦❢ ●✐❧❧❡s♣✐❡ ❬●■❧❧❡s♣✐❡ ✶✾✼✻❪ t♦ s✐♠✉❧❛t❡ t❤❡

❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ s②st❡♠✳ ❚❤❡ ♣r♦❝❡❞✉r❡ ②✐❡❧❞s ❛♥ ❛s②♥❝❤r♦♥♦✉s r❛♥❞♦♠ ❡①❡❝✉t✐♦♥ ♦❢

t❤❡ ❡✈❡♥ts ❛♥❞ s✉♣♣♦s❡ t❤❛t ♦♥❡ ❡✈❡♥t ♦❝❝✉rs ❛t ❛ t✐♠❡✳ ■t ✐t❡r❛t❡s ♦✈❡r t❤❡ ❢♦❧❧♦✇✐♥❣

st❡♣s✿

✶✳ ❙❡t t❤❡ t✐♠❡ t♦ t = 0

✷✳ ❈❛❧❝✉❧❛t❡✿

✭❛✮ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❞❡t❛❝❤♠❡♥t r❛t❡s ♦❢ t❤❡ ❜❛❝t❡r✐❛

✭❜✮ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ❞❡t❛❝❤♠❡♥t r❛t❡s ♦❢ t❤❡ ♣♦❧②♠❡r

✭❝✮ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ♠♦t✐❧✐t② r❛t❡s ♦❢ t❤❡ ❜❛❝t❡r✐❛

✸✳ ❈❛❧❝✉❧❛t❡ t❤❡ s✉♠s r1✱ r2 ❛♥❞ r3 ✇❤✐❝❤ ❛r❡ r❡s♣❡❝t✐✈❡❧② t❤❡ s✉♠s ♦❢ t❤❡ ✐♥❞✐✈✐❞✲

✉❛❧ r❛t❡s ♦❢ ❜❛❝t❡r✐❛ ❞❡t❛❝❤♠❡♥t✱ ♣♦❧②♠❡r ❞❡t❛❝❤♠❡♥t ❛♥❞ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t②✳

✹✳ ❈❛❧❝✉❧❛t❡ t❤❡ s✉♠s r4 ❛♥❞ r5 ✇❤✐❝❤ ❛r❡ r❡s♣❡❝t✐✈❡❧② t❤❡ s✉♠ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧

❞✐✈✐s✐♦♥ r❛t❡s ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❛♥❞ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ♣r♦❞✉❝t✐♦♥ r❛t❡s ♦❢ ♣♦❧②♠❡r

✺✳ ❈❛❧❝✉❧❛t❡ t❤❡ ♦✈❡r❛❧❧ r❛t❡ ♦❢ ❡✈❡♥ts ✿ r = r1 + r2 + r3 + r4 + r5

✻✳ ❈❤♦♦s❡ t❤❡ ✇❛✐t✐♥❣ t✐♠❡ τ ❢♦r t❤❡ ♥❡①t ❡✈❡♥t t♦ ♦❝❝✉r ❛❝❝♦r❞✐♥❣ t♦ τ = −1

r lnλ

✇❤❡r❡ 0 < λ ≤ 1 ✐s ❛ ✉♥✐❢♦r♠❧② ❞✐str✐❜✉t❡❞ r❛♥❞♦♠ ♥✉♠❜❡r

✼✳ ❈❤♦♦s❡ ❛♥ ❡✈❡♥t ✇✐t❤ t❤❡ ❢♦❧❧♦✇✐♥❣ ♣r♦❜❛❜✐❧✐t✐❡s✿

✭❛✮ ❛ ❞❡t❛❝❤♠❡♥t ♦❢ ❛ ❜❛❝t❡r✐✉♠ ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r1/r

✭❜✮ ❛ ❞❡t❛❝❤♠❡♥t ♦❢ ❛ ♣♦❧②♠❡r ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r2/r

✭❝✮ ❛ ❞✐✈✐s✐♦♥ ♦❢ ❛ ❜❛❝t❡r✐❛ ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r3/r

✭❞✮ ❛ ♣r♦❞✉❝t✐♦♥ ♦❢ ❛ ♣♦❧②♠❡r ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r4/r

✭❡✮ ❛ ❞✐s♣❧❛❝❡♠❡♥t ♦❢ ❛ ❜❛❝t❡r✐✉♠ ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r5/r

✽✳ ❙❡❧❡❝t ❛♥ ✐♥❞✐✈✐❞✉❛❧✿

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✾✵ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

✭❛✮ ■❢ t❤❡ ❡✈❡♥t ✐s ❛ ❞❡t❛❝❤♠❡♥t ♦❢ ♣♦❧②♠❡r t❤❛♥ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ j ✐s

s❡❧❡❝t❡❞ ✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r2j/r ✇❤❡r❡ r2j ✐s t❤❡ ❞❡t❛❝❤♠❡♥t r❛t❡ ♦❢ t❤❡

✐♥❞✐✈✐❞✉❛❧ j

✭❜✮ ■❢ t❤❡ ❡✈❡♥t ✐s ❛ ❞❡t❛❝❤♠❡♥t ♦❢ ❛ ❜❛❝t❡r✐✉♠ t❤❛♥ ❛ ❜❛❝t❡r✐✉♠ i ✐s s❡❧❡❝t❡❞

✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r1i/r ✇❤❡r❡ r1i ✐s t❤❡ ❞❡t❛❝❤♠❡♥t r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧

i

✭❝✮ ■❢ t❤❡ ❡✈❡♥t ✐s ❛ ♣r♦❞✉❝t✐♦♥ ♦❢ ♣♦❧②♠❡r t❤❛♥ ❜❛❝t❡r✐✉♠ i ✐s s❡❧❡❝t❡❞ ✇✐t❤

❛ ♣r♦❜❛❜✐❧✐t② r4i/r ✇❤❡r❡ r4i ✐s t❤❡ ♣r♦❞✉❝t✐♦♥ r❛t❡ ♦❢ t❤❡ ♦❢ ♣♦❧②♠❡r ♦❢

t❤❡ ✐♥❞✐✈✐❞✉❛❧ i

✭❞✮ ■❢ t❤❡ ❡✈❡♥t ✐s ❛ ❞✐✈✐s✐♦♥ ♦❢ ❛ ❜❛❝t❡r✐✉♠ t❤❛♥ ❛ ❜❛❝t❡r✐✉♠ i ✐s s❡❧❡❝t❡❞

✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r3i/r ✇❤❡r❡ r3i ✐s t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i

✭❡✮ ■❢ t❤❡ ❡✈❡♥t ✐s ❛ ❞✐s♣❧❛❝❡♠❡♥t ♦❢ ❛ ❜❛❝t❡r✐✉♠ t❤❛♥ ❛ ❜❛❝t❡r✐✉♠ i ✐s s❡❧❡❝t❡❞

✇✐t❤ ❛ ♣r♦❜❛❜✐❧✐t② r5i/r ✇❤❡r❡ r5i ✐s t❤❡ ♠♦t✐❧✐t② r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i

✾✳ P❡r❢♦r♠ t❤❡ s❡❧❡❝t❡❞ ❡✈❡♥t ♦♥ t❤❡ s❡❧❡❝t❡❞ ✐♥❞✐✈✐❞✉❛❧

✶✵✳ ❯♣❞❛t❡ t✐♠❡ ❛❝❝♦r❞✐♥❣ t♦ t = t+ τ

✶✶✳ ❈♦♥t✐♥✉❡ ❢r♦♠ st❡♣ ✷ ✉♥t✐❧ t < tend

✻✳✶✳✷ ❉❡t❛✐❧s

✻✳✶✳✷✳✶ ❙✉❜♠♦❞❡❧s

• ❉✐✈✐s✐♦♥✿ ❲❡ s✉♣♣♦s❡ t❤❛t t❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡ t❤❛t ❛ ❜❛❝t❡r✐✉♠

i ✐♥ ♣♦s✐t✐♦♥ xi ♣r♦❞✉❝❡s ❛ ♥❡✇ ❝❡❧❧ ❧♦❝❛t❡❞ ✐♥ ♣♦s✐t✐♦♥ x′ ✐s ❣✐✈❡♥ ❜②✿

Bb(xi, x′) = b1K

(

||xi − x′||

wb

)

✭✻✳✶✮

❚❤❡ ♣❛r❛♠❡t❡r b1 ✐s ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❛♥❞

K(||xi − x′||/wb) ✐s ❛ ✉♥✐❢♦r♠ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧ ✇✐t❤ ❛ ✇✐♥❞♦✇ s✐❞❡ wb✳ ❚❤❡

❣❡♥❡r❛❧ ❢♦r♠ ♦❢ t❤✐s ❦❡r♥❡❧ ❢♦r ❛ ✇✐♥❞♦✇ s✐❞❡ w ❣✐✈❡♥ ❜②✿

K

(

||x− x′||

w

)

=

{

1/w ✐❢ ||x− x′|| < w

0 ❡❧s❡✭✻✳✷✮

❚❤❡ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧ ❣✐✈❡s t❤❡ ♣r♦❜❛❜✐❧✐t② t❤❛t t❤❡ ♥❡✇❧② ❢♦r♠❡❞ ✐♥❞✐✈✐❞✉❛❧

❞✐s♣❡rs❡s ✐♥st❛♥t❛♥❡♦✉s❧② ❛❢t❡r t❤❡ ❞✐✈✐s✐♦♥ ❡✈❡♥t t♦ t❤❡ ❧♦❝❛t✐♦♥ x′✳ ❚❤✐s

♣r♦❜❛❜✐❧✐t② ❞❡♣❡♥❞s ♦♥ t❤❡ ❞✐st❛♥❝❡ ||xi − x′|| ❛♥❞ t❤❡ s✐③❡ ♦❢ t❤❡ ❞✐s♣❡rs✐♦♥

❦❡r♥❡❧ wb✳

• P♦❧②♠❡r ♣r♦❞✉❝t✐♦♥✿ ❲❡ s✉♣♣♦s❡ t❤❛t t❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡

t❤❛t ❛ ❜❛❝t❡r✐✉♠ ✐♥❞✐✈✐❞✉❛❧ i ✐♥ ♣♦s✐t✐♦♥ xi ♣r♦❞✉❝❡s ❛ ♥❡✇ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡

✐♥ ♣♦s✐t✐♦♥ x′ ✐s ❣✐✈❡♥ ❜②✿

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✻✳✶✳ ❉❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ✾✶

Bp(xi, x′) = b2K

(

||xi − x′||

wb

)

✭✻✳✸✮

❚❤❡ ♣❛r❛♠❡t❡r b2 ✐s ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ r❛t❡✳ ❲❡ ✉s❡

t❤❡ s❛♠❡ ❞✐s♣❡rs✐♦♥ ❦❡r♥❡❧ ❛s ❢♦r t❤❡ ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥✳

• ❇❛❝t❡r✐❛ ❞❡t❛❝❤♠❡♥t✿ ❲❡ s✉♣♣♦s❡ t❤❛t t❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡

t❤❛t ❛ ❜❛❝t❡r✐✉♠ i ✐♥ ♣♦s✐t✐♦♥ xi ❞❡t❛❝❤❡s ❞❡♣❡♥❞s ♦♥ t❤❡ ❧♦❝❛❧ ❝♦♥❝❡♥tr❛t✐♦♥

♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ✐♥ xi ❞❡♥♦t❡❞ ploc(xi)✳ ❚❤✐s ♣r♦❜❛❜✐❧✐t② ✐s ❣✐✈❡♥ ❜②✿

Db(xi) = [d1 + d′1ploc(xi)] ✭✻✳✹✮

❚❤❡ ♣❛r❛♠❡t❡rs d1 ❛♥❞ d′1 ❛r❡ t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❛♥❞ t❤❡ ❞❡♥s✐t②✲

❞❡♣❡♥❞❛♥t ❞❡t❛❝❤♠❡♥t r❛t❡s r❡s♣❡❝t✐✈❡❧②✳ ❚❤❡ t❡r♠ ploc(xi) ✐s t❤❡ ❧♦❝❛❧ ❞❡♥s✐t②

✭❞❡✜♥❡❞ ✐♥ ♠♦r❡ ❞❡t❛✐❧s ❜❡❧♦✇✮ ❛s ♣❡r❝❡✐✈❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ xi✳

• P♦❧②♠❡r ❞❡t❛❝❤♠❡♥t✿ ❲❡ s✉♣♣♦s❡ t❤❛t t❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡

t❤❛t ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ j ✐♥ ♣♦s✐t✐♦♥ xj ❞❡t❛❝❤ ❞❡♣❡♥❞s ♦♥ t❤❡ ❧♦❝❛❧ ❝♦♥❝❡♥✲

tr❛t✐♦♥ ♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ✐♥ xj ❞❡♥♦t❡❞ ploc(xj)✳ ❚❤✐s ♣r♦❜❛❜✐❧✐t② ✐s ❣✐✈❡♥

❜②✿

Dp(xj) = [d2 + d′2(ploc(xj))] ✭✻✳✺✮

❚❤❡ ♣❛r❛♠❡t❡rs d2 ❛♥❞ d′2 ❛r❡ t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❛♥❞ t❤❡ ❞❡♥s✐t②✲

❞❡♣❡♥❞❛♥t ❞❡t❛❝❤♠❡♥t r❛t❡s r❡s♣❡❝t✐✈❡❧②✳ ❚❤❡ t❡r♠ ploc(xi) ✐s t❤❡ ❧♦❝❛❧ ❞❡♥s✐t②

✭❞❡✜♥❡❞ ✐♥ ♠♦r❡ ❞❡t❛✐❧s ❜❡❧♦✇✮ ❛s ♣❡r❝❡✐✈❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ xj ✳

• ❈❛❧❝✉❧❛t✐♦♥ ♦❢ t❤❡ ♣❡r❝❡✐✈❡❞ ❧♦❝❛❧ ❞❡♥s✐t②✿ ❚❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ ❛

♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ j ❧♦❝❛t❡❞ ✐♥ xj t♦ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ♣❡r❝❡✐✈❡❞ ❜②

❛♥ ✐♥❞✐✈✐❞✉❛❧ ✭❜❛❝t❡r✐❛ ♦r ♣♦❧②♠❡r✮ i ❧♦❝❛t❡❞ ✐♥ xi ✐s ✇❡✐❣❤t❡❞ ❜② ❛♥ ✐♥t❡r❛❝✲

t✐♦♥ ❦❡r♥❡❧ K(||xi − xj ||/wd)✳ ❚❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ♣❡r❝❡✐✈❡❞ ❜② t❤❡

✐♥❞✐✈✐❞✉❛❧ ✐♥ xi ✐s ❝❛❧❝✉❧❛t❡❞ ❜② s✉♠♠✐♥❣ t❤❡ ✇❡✐❣❤t❡❞ ❝♦♥tr✐❜✉t✐♦♥s ♦❢ ❛❧❧ t❤❡

♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ✐♥ t❤❡ s②st❡♠✿

ploc(xi) =

j=np∑

j=0

K

(

||xi − xj ||

wd

)

✭✻✳✻✮

■❢ t❤❡ ♣❛rt✐❝❧❡ ✐♥ xi ✐s ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ✐ts ❝♦♥tr✐❜✉t✐♦♥ t♦ t❤❡ ♣❡r❝❡✐✈❡❞

❧♦❝❛❧ ❞❡♥s✐t② ✐s ♥♦t ❝♦✉♥t❡❞✳

• ❇❛❝t❡r✐❛ ♠♦t✐❧✐t②✿ ❚❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡ t❤❛t ❛ ❜❛❝t❡r✐✉♠ i ✐♥

xi ♠♦✈❡s t♦ ❛ ♣♦s✐t✐♦♥ x′ ✐s ❣✐✈❡♥ ❜②✿

M(xi, x′) = [m1 −m2ploc(xi)]K

(

||xi − x′||

wm

)

✭✻✳✼✮

Page 105: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✾✷ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

❲❤❡r❡ m1 ❛♥❞ m2 ❛r❡ r❡s♣❡❝t✐✈❡❧② t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❛♥❞ t❤❡ ❞❡♥s✐t②

❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡s ❛♥❞ K(||xi − x′||/wm) ❛ ✉♥✐❢♦r♠ ♠♦t✐❧✐t② ❦❡r♥❡❧✳

✻✳✶✳✷✳✷ ■♥✐t✐❛❧✐③❛t✐♦♥

❚❤❡ ♠♦❞❡❧ ✐s ✐♥✐t✐❛❧✐③❡❞ ✇✐t❤ nb(t = 0) = 1000 ❜❛❝t❡r✐❛❧ ❝❡❧❧s ❞✐str✐❜✉t❡❞ ✉♥✐❢♦r♠❧②

♦✈❡r t❤❡ ❞♦♠❛✐♥✳ ■♥✐t✐❛❧❧② t❤❡r❡ ❛r❡ ♥♦ ♣♦❧②♠❡r ♣❛rt✐❝❧❡s ✐♥ t❤❡ ❞♦♠❛✐♥ ✭np(t = 0) =

0✮

✻✳✶✳✷✳✸ ▼♦❞❡❧ ♣❛r❛♠❡t❡rs

❚❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs ❛r❡ s✉♠♠❛r✐③❡❞ ✐♥ t❛❜❧❡ ✻✳✸✳ ❯♥❧❡ss ❡①♣❧✐❝✲

✐t❧② s♣❡❝✐✜❡❞✱ ✇❡ ✉s❡ t❤❡ ❞❡❢❛✉❧t ♣❛r❛♠❡t❡r ✈❛❧✉❡s ✐♥ t❛❜❧❡ ✻✳✸✳

✻✳✷ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥

❲❡ ♣r♦♣♦s❡ t♦ ❞❡✈❡❧♦♣ ❛ ❞❡t❡r♠✐♥✐st✐❝ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧ t❤❛t ❛♣♣r♦①✐♠❛t❡ t❤❡

❞②♥❛♠✐❝ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ❞❡s❝r✐❜❡❞ ✐♥ t❤❡ ♣r❡✈✐♦✉s s❡❝t✐♦♥ ✉s✐♥❣ ♠♦✲

♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ t❡❝❤♥✐q✉❡s✳

✻✳✷✳✶ ❋✐rst ♠♦♠❡♥t ❞②♥❛♠✐❝s

❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✜rst ♠♦♠❡♥t ✭❛✈❡r❛❣❡ ❞❡♥s✐t✐❡s ♦❢ ❜❛❝t❡r✐❛ ❛♥❞ ♣♦❧②♠❡r✮ ✐s ❣✐✈❡♥

❜② t❤❡ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥s✿

dNb

dt= (b1 − d1)Nb − d′1

Cbp(ξ)K

(

||ξ||

wd

)

dξ ✭✻✳✽✮

dNp

dt= b2Nb − d2Np − d′2

Cpp(ξ)K

(

||ξ||

wd

)

dξ ✭✻✳✾✮

❊q✉❛t✐♦♥s ✻✳✽ ❛♥❞ ✻✳✾ ❞❡s❝r✐❜❡ r❡s♣❡❝t✐✈❡❧② t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t②

♦❢ ❜❛❝t❡r✐❛ Nb ❛♥❞ ♣♦❧②♠❡r Np✳ ❚❤❡ ✐♥t❡❣r❛❧ t❡r♠s ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ❛r❡ t❤❡

♥❡✐❣❤❜♦r❤♦♦❞✲❞❡♣❡♥❞❡♥t ❝♦♠♣♦♥❡♥ts ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t✳ ❚❤❡② ✐♥✈♦❧✈❡ r❡s♣❡❝t✐✈❡❧②

t❤❡ ♣❛✐r ❞❡♥s✐t✐❡s Cbp(ξ) ❛♥❞ Cpp(ξ) ❛♥❞ ❛♥ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ||/wd)✳ ❚❤❡s❡

t❡r♠s ❡♥❝♦♠♣❛ss t❤❡ ❡✛❡❝t ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ✐♥ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢

❜❛❝t❡r✐❛✱ ❛s ❣✐✈❡♥ ❜② Cbp(ξ)✱ ❛♥❞ ✐♥ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡✱ ❛s

❣✐✈❡♥ ❜② Cpp(ξ)✱ ✇❡✐❣❤t❡❞ ❜② t❤❡ ✉♥✐❢♦r♠ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ||/wd)✳ ◆♦t❡ t❤❛t

✐❢ t❤❡ s✐③❡ wd ♦❢ ✉♥✐❢♦r♠ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ ✐s ❡q✉❛❧ t♦ t❤❡ s✐❞❡ ♦❢ t❤❡ ❞♦♠❛✐♥ t❤❛♥

❛ ❜❛❝t❡r✐✉♠ ✭r❡s♣❡❝t✐✈❡❧② ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡✮ ❡①♣❡r✐❡♥❝❡s ❡q✉❛❧❧② t❤❡ ❡✛❡❝t ♦❢ ❛❧❧

t❤❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ✇✐t❤✐♥ t❤❡ ❞♦♠❛✐♥✳ ❚❤✐s r❡❞✉❝❡s ❡q✉❛t✐♦♥s ✻✳✽ ❛♥❞ ✻✳✾ t♦ t❤❡

❢♦❧❧♦✇✐♥❣ ♠❡❛♥✲✜❡❧❞ s②st❡♠✿

dNb

dt= (b1 − d1)Nb − d′1NbNp ✭✻✳✶✵✮

dNp

dt= b2Nb − d2Np − d′2NpNp ✭✻✳✶✶✮

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✻✳✷✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ✾✸

❚❤❡ ♠❡❛♥✲✜❡❧❞ ❡q✉❛t✐♦♥s ❝❛♥ ❛❧s♦ ❜❡ ♦❜t❛✐♥❡❞ ✐❢ t❤❡ ♣♦s✐t✐♦♥ ♦❢ t❤❡ ❜❛❝t❡r✐❛❧

❝❡❧❧s ✭r❡s♣❡❝t✐✈❡❧② t❤❡ ♣♦❧②♠❡r✐❝ ❝❡❧❧s✮ ❛r❡ ♥♦t ❝♦rr❡❧❛t❡❞ ✇✐t❤ t❤❡ ♣♦s✐t✐♦♥ ♦❢ t❤❡

♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s✳ ■♥ t❤✐s ❝❛s❡ t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs ❢♦r♠❡❞ ✇✐t❤ ❛ ❢♦❝❛❧ ❜❛❝t❡r✐✉♠

✭r❡s♣❡❝t✐✈❡❧② ❛ ❢♦❝❛❧ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s✮ ✇✐t❤ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ❧♦❝❛t❡❞ ❛t ❛

✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ ❢r♦♠ t❤❡ ❢♦❝❛❧ ♣❛rt✐❝❧❡ ✐s ❡q✉❛❧ t♦ t❤❡ ♣r♦❞✉❝t ♦❢ t❤❡ ❛✈❡r❛❣❡

❞❡♥s✐t✐❡s NbNp ✭r❡s♣❡❝t✐✈❡❧② NpNp✮✳ ❙♣❛t✐❛❧ ♣❛tt❡r♥s ❢♦r♠❛t✐♦♥ ❛♥❞ s♠❛❧❧ ✐♥t❡r❛❝✲

t✐♦♥ ❦❡r♥❡❧ ♠❛② ❝❛✉s❡ ❛ ❞❡♣❛rt✉r❡ ❢r♦♠ t❤❡ ♠❡❛♥✲✜❡❧❞ ♠♦❞❡❧✳ ❚❤❡ s②st❡♠ ❢♦r♠❡❞

✇✐t❤ ❡q✉❛t✐♦♥s ✻✳✽ ❛♥❞ ✻✳✾ ✐s ♥♦t ❝❧♦s❡❞ ❛♥❞ ♥❡❡❞ t♦ ❜❡ ❝♦✉♣❧❡❞ t♦ t❤❡ ❞②♥❛♠✐❝ ♦❢

Cbp(ξ) ❛♥❞ Cpp(ξ)✳

✻✳✷✳✷ ❙❡❝♦♥❞ ♠♦♠❡♥t ❞②♥❛♠✐❝s

❚❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s Cbb(ξ)✱ Cbp(ξ) ❛♥❞ Cpp(ξ) ❝❤❛r❛❝t❡r✐③❡ t❤❡ s♣❛t✐❛❧

♣❛tt❡r♥ ❢♦r♠❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛ ❛♥❞ t❤❡ ♣♦❧②♠❡r✳ ❚❤❡② ♠❡❛s✉r❡ r❡s♣❡❝t✐✈❡❧② t❤❡

❞❡♥s✐t✐❡s ♦❢ ♣❛✐rs ❢♦r♠❡❞ ✇✐t❤ t✇♦ ❜❛❝t❡r✐❛✱ ❛ ❜❛❝t❡r✐✉♠ ❛♥❞ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡

♦r t✇♦ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ❛t ❞✐✛❡r❡♥t ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ✳ ❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡s❡

❢✉♥❝t✐♦♥s ❛❝❝♦✉♥t ❢♦r t❤❡ ✜✈❡ ♣r♦❝❡ss❡s✿ ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥✱ ♣r♦❞✉❝t✐♦♥ ♦❢ ♣♦❧②♠❡r✐❝

♣❛rt✐❝❧❡s✱ ❜❛❝t❡r✐❛ ❞❡t❛❝❤♠❡♥t✱ ♣♦❧②♠❡r ❞❡t❛❝❤♠❡♥t ❛♥❞ ♠♦t✐❧✐t② ♦❢ t❤❡ ❜❛❝t❡r✐❛✳

✻✳✷✳✷✳✶ ❉②♥❛♠✐❝ ♦❢ t❤❡ ❜❛❝t❡r✐❛✲❜❛❝t❡r✐❛ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥

❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ❜❛❝t❡r✐❛✲❜❛❝t❡r✐❛ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ Cbb(ξ) ✐s ❣✐✈❡♥ ❜②✿

dCbb(ξ)

dt=

(

dCbb(ξ)

dt

)

division

+

(

dCbb(ξ)

dt

)

detachment

+

(

dCbb(ξ)

dt

)

motility

✭✻✳✶✷✮

❚❤❡ t❡r♠s ✐♥ t❤❡ r✐❣❤t ❤❛♥❞ s✐❞❡ ❞❡♥♦t❡s ❢♦r t❤❡ ❡✛❡❝t ♦❢ t❤r❡❡ ♣r♦❝❡ss❡s t❤❛t

♠❛② ♠♦❞✐❢② t❤❡ ❜❛❝t❡r✐❛ ♣❛tt❡r♥ ❛♥❞ ✇❤✐❝❤ ❛r❡ t❤❡ ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥✱ ❞❡t❛❝❤♠❡♥t

❛♥❞ ♠♦t✐❧✐t② ❡✈❡♥ts✳ ❚❤❡ ❡✛❡❝t ♦❢ ❞✐✈✐s✐♦♥ ❡✈❡♥ts ♦♥ Cbb(ξ) ✐s ❣✐✈❡♥ ❜② t❤❡ ❢♦❧❧♦✇✐♥❣

❡q✉❛t✐♦♥✿

(

dCbb(ξ)

dt

)

division

= +2b1NbK

(

||ξ||

wb

)

+2b1

Cbb(ξ + ξ′)K

(

||ξ′||

wb

)

dξ′ ✭✻✳✶✸✮

• ❚❤❡ ✜rst t❡r♠ ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❞✐✈✐s✐♦♥ ♦❢ ❛ ❜❛❝t❡r✐✉♠

i ♣r♦❞✉❝✐♥❣ ❛ ♥❡✇ ❝❡❧❧ j ❧♦❝❛t❡❞ ❛t ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ✳ ❚❤✐s ❡✈❡♥t ②✐❡❧❞s ❛

♥❡✇ ♣❛✐r ♦❢ ❜❛❝t❡r✐❛ s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ✳ ❚❤❡ r❛t❡ ❛t ✇❤✐❝❤

s✉❝❤ ❞✐✈✐s✐♦♥ ❡✈❡♥ts ♦❝❝✉r ✐s ♦❜t❛✐♥❡❞ ❜② ♠✉❧t✐♣❧②✐♥❣ t❤❡ ❞❡♥s✐t② ♦❢ ❛✈❡r❛❣❡

❜❛❝t❡r✐❛ Nb ❜② t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ b1✳ ❚❤❡♥ ✇❡ ♠✉❧t✐♣❧② ❜② t❤❡ ♣r♦❜❛❜✐❧✐t②

K(||ξ||/wb) t❤❛t t❤❡ ♥❡✇❧② ❢♦r♠❡❞ ❝❡❧❧s ❛r❡ ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ ❢r♦♠ t❤❡

♣❛r❡♥t ❝❡❧❧✳ ❚❤❡ ❢❛❝t♦r 2 ❛❝❝♦✉♥ts ❢♦r ♥❡✇❧② ❢♦r♠❡❞ ❝❡❧❧s ❛t ❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡

−ξ ✇❤✐❝❤ ❛❧s♦ ❢♦r♠ ❛ ♥❡✇ ♣❛r (j, i) ❛t ❞✐st❛♥❝❡ ξ✳

Page 107: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✾✹ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

• ❚❤❡ s❡❝♦♥❞ t❡r♠ ❢♦❝✉s❡s ♦♥ t❤❡ ♥❡✇ ♣❛✐r t❤❛t t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧ ♦❢ ❛ ♣❛r❡♥t

❜❛❝t❡r✐✉♠ i ❢♦r♠ ✇✐t❤ ❛ ❜❛❝t❡r✐✉♠ j ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ + ξ′ ❢r♦♠ i✳ ❚❤❡

❞❡♥s✐t② ♦❢ (i, j) ♣❛✐rs ✐s Cbb(ξ + ξ) ❛♥❞ t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ✐s b1✳ ▼✉❧t✐♣❧②✐♥❣

t❤❡s❡ t✇♦ ❢❛❝t♦rs ✇✐t❤ t❤❡ ♣r♦❜❛❜✐❧✐t② K(||ξ′||/wb) t❤❛t t❤❡ ♥❡✇❧② ❢♦r♠❡❞ ❝❡❧❧s

✐s ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ′ ❢r♦♠ i ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ♣♦ss✐❜❧❡ ❞✐st❛♥❝❡s ξ′

❣✐✈❡s t❤❡ s❡❝♦♥❞ t❡r♠✳ ❲❡ ❛❧s♦ t❛❦❡ ✐♥t♦ ❝♦♥s✐❞❡r❛t✐♦♥ t❤❛t ❛♥❛❧♦❣♦✉s ❡✈❡♥t

❝❛♥ ♦❝❝✉r t♦ t❤❡ ✐♥❞✐✈✐❞✉❛❧ j ❜② ♠✉❧t✐♣❧②✐♥❣ t❤❡ s❡❝♦♥❞ t❡r♠ ❜② ❛ ❢❛❝t♦r 2✳

❚❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t ❡✈❡♥ts ♦❢ ❜❛❝t❡r✐❛ t♦ t❤❡ ❞②♥❛♠✐❝ ♦❢ Cbb(ξ)

✐s ❣✐✈❡♥ ❜②✿

(

dCbb(ξ)

dt

)

detachment

= −2d1Cbb(ξ)

−2d′1

K

(

||ξ′′||

wd

)

Tbbp(ξ, ξ′′)dξ′′ ✭✻✳✶✹✮

• ❚❤❡ ✜rst t❡r♠ ✐♥ t❤❡ r✐❣❤t ❤❛♥❞ s✐❞❡ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❞❡t❛❝❤♠❡♥t ♦❢ t❤❡ ❝❡❧❧ i

✐♥ t❤❡ ♣❛✐r (i, j)✳ ❙✉❝❤ ❡✈❡♥ts ♦❝❝✉r ❛t ❛ r❛t❡ d1✳ ▼✉❧t✐♣❧②✐♥❣ d1 ❜② t❤❡ ❞❡♥s✐t②

Cbb(ξ) ♦❢ (i, j) ♣❛✐rs ❛t ❞✐st❛♥❝❡ ξ ❣✐✈❡s t❤❡ r❡s✉❧t✐♥❣ ❞❡❝r❡❛s❡ ✐♥ t❤❛t ❞❡♥s✐t②✳

❚❤❡ ❢❛❝t♦r 2 ❛❝❝♦✉♥ts t❤❛t ❛♥❛❧♦❣♦✉s ❡✈❡♥t ❝❛♥ ♦❝❝✉r ❢♦r t❤❡ ✐♥❞✐✈✐❞✉❛❧ j✳

• ❚❤❡ s❡❝♦♥❞ t❡r♠ ✐s t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t t❡r♠ t❤❛t ❛❝❝♦✉♥ts ❢♦r

t❤❡ ♣r❡s❡♥❝❡ ♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ✐♥ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡ ❜❛❝t❡r✐❛✳ ❚❤❡

❞❡t❛❝❤♠❡♥t ♦❢ ❛ ❜❛❝t❡r✐✉♠ i ♦❢ t❤❡ (i, j) ♣❛✐r ❝❛♥ r❡s✉❧t ❢r♦♠ t❤❡ ♣r❡s❡♥❝❡ ♦❢

♣♦❧②♠❡r ♣❛rt✐❝❧❡ k ❛t ❛ ❞✐st❛♥❝❡ ξ′′ ❢r♦♠ i✳ ❙✉❝❤ tr✐♣❧❡t ❝♦♥✜❣✉r❛t✐♦♥ ♦❝❝✉rs

❛t ❛ ❞❡♥s✐t② Tbbp(ξ, ξ′′)✳ ❚❤❡ ❝✉♠✉❧❛t✐✈❡ ❡✛❡❝t ♦❢ t❤❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s k

s✐t✉❛t❡❞ ❛t ❞✐✛❡r❡♥t ❞✐st❛♥❝❡s ξ′′ ❢r♦♠ t❤❡ ❝❡❧❧ i ✐s ♦❜t❛✐♥❡❞ ❜② ✇❡✐❣❤t✐♥❣ t❤❡

tr✐♣❧❡t ❞❡♥s✐t② ✇✐t❤ K(||ξ′′||/wd) ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ✐♥t❡r❛❝t✐♦♥ ❞✐st❛♥❝❡s

ξ′′✳ ▼✉❧t✐♣❧②✐♥❣ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ✇✐t❤ t❤❡ ❞❡♥s✐t②✲

❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡ ♦❢ t❤❡ ❜❛❝t❡r✐❛ d′1 ❣✐✈❡s t❤❡ s❡❝♦♥❞ t❡r♠✳ ❚❤❡

❢❛❝t♦r 2 ❛❝❝♦✉♥ts ❢♦r t❤❡ ❛♥❛❧♦❣♦✉s ❡✈❡♥t t❤❛t ❝❛♥ ♦❝❝✉r ❢♦r t❤❡ ❝❡❧❧ j ✐♥ t❤❡

t❤❡ ♣❛✐r (i, j)✳

❚❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧✐t② t♦ t❤❡ ❞②♥❛♠✐❝ ♦❢ Cbb(ξ) ✐s ❣✐✈❡♥ ❜② t❤❡ ❢♦❧❧♦✇✐♥❣

❡q✉❛t✐♦♥✿

(

dCbb(ξ)

dt

)

motility

= −2m1Cbb(ξ) ✭✻✳✶✺✮

+2m1

K

(

||ξ′||

wm

)

Cbb(ξ + ξ′)dξ′

+2m2

K

(

||ξ′′||

wd

)

Tbbp(ξ, ξ′′)dξ′′

−2m2

∫ ∫

K

(

||ξ′||

wm

)

K

(

||ξ′′||

wd

)

Tbbp(ξ + ξ′, ξ′′)dξ′dξ′′

Page 108: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✻✳✷✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ✾✺

• ❲❤❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ♠♦✈❡s✱ t❤❡ ♦r✐❣✐♥❛❧ ♣❛✐r (i, j) ❛t ❞✐st❛♥❝❡ ξ ✐s ❞❡str♦②❡❞✳

❚❤❡ ✜rst t❡r♠ ✐♥ t❤❡ r✐❣❤t ❤❛♥❞ s✐❞❡ ❛❝❝♦✉♥ts ❢♦r t❤✐s ♣r♦❝❡ss ❜② ♠✉❧t✐♣❧②✐♥❣

t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡ ♦❢ m1 ❜② t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs Cbb(ξ) ♦❢

t❤❡ ♦r✐❣✐♥❛❧ ♣❛✐r ❝♦♥✜❣✉r❛t✐♦♥✳

• ❖♥ t❤❡ ♦t❤❡r ❤❛♥❞ ❛ ♥❡✇ (i, j) ♣❛✐r ♦❢ ❜❛❝t❡r✐❛ ✐s ❝r❡❛t❡❞ ❛t ❞✐st❛♥❝❡ ξ ✇❤❡♥ t❤❡

❝❡❧❧ i ❛t ♦r✐❣✐♥❛❧❧② ❛t ❛ ❞✐st❛♥❝❡ ξ+ ξ′ ❢r♦♠ t❤❡ ❝❡❧❧ j ♠♦✈❡s ❛ ❞✐st❛♥❝❡ ξ′✳ ❚❤✐s

❡✛❡❝t ✐s ❝❛♣t✉r❡❞ ❜② t❤❡ s❡❝♦♥❞ t❡r♠✱ ✇❤✐❝❤ ✇❡✐❣❤ts t❤❡ ❞❡♥s✐t② Cbb(ξ + ξ′)

♦❢ t❤❡ ♦r✐❣✐♥❛❧ ♣❛✐r ❝♦♥✜❣✉r❛t✐♦♥ ✇✐t❤ t❤❡ ♠♦t✐❧✐t② ❦❡r♥❡❧ UK(||ξ′||/wm) ❛♥❞

✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ♣♦ss✐❜❧❡ ♠♦t✐❧✐t② ❞✐st❛♥❝❡s ξ′✳

• ❚❤❡ t❤✐r❞ t❡r♠ ❝♦rr❡❝ts t❤❡ ✜rst t❡r♠ ❜② ❛❝❝♦✉♥t✐♥❣ ❢♦r t❤❡ ♣♦ss✐❜❧❡ ♣r❡s❡♥❝❡

♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ✐♥ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡ ❝❡❧❧ ✐♥ t❤❡ ♣❛✐r (i, j) ♦r✐❣✐♥❛❧❧②

❛t ❛ ❞✐st❛♥❝❡ ξ✳ ❚❤❡ ♠♦t✐❧✐t② ♦❢ i ✐♥ t❤❡ ♣❛✐r (i, j) ✐s r❡❞✉❝❡❞ ❜② t❤❡ ♣r❡s❡♥❝❡

♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ k ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ′′ ❢r♦♠ i✳ ❚❤❡ ❞❡♥s✐t② tr✐♣❧❡t

❢♦r♠❡❞ ✇✐t❤ t✇♦ ❝❡❧❧s s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ ❛♥❞ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ❛t

❛ ❞✐st❛♥❝❡ ξ′′ ❢r♦♠ i ✐s Tbbp(ξ, ξ′′)✳ ❲❡✐❣❤t✐♥❣ t❤✐s ❞❡♥s✐t② ❜② t❤❡ ✐♥t❡r❛❝t✐♦♥

❦❡r♥❡❧ K(||ξ′′||/wd) ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′′ ❣✐✈❡s t❤❡ t❤✐r❞ t❡r♠✳

❚❤❡ ❢❛❝t♦r ✷ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❛♥❛❧♦❣♦✉s ❡✈❡♥t t❤❛t ❝❛♥ ♦❝❝✉r ❢♦r t❤❡ ❝❡❧❧ j✳

• ❚❤❡ ❧❛st t❡r♠ ❝♦rr❡❝ts t❤❡ s❡❝♦♥❞ t❡r♠ ❜② ❛❝❝♦✉♥t✐♥❣ ❢♦r ♠♦t✐❧✐t② r❡❞✉❝t✐♦♥ ♦❢

t❤❡ ❝❡❧❧ i ♦r✐❣✐♥❛❧❧② ❛t ❛ ❞✐st❛♥❝❡ ξ+ ξ′ ❢r♦♠ t❤❡ ❝❡❧❧ j ❞✉❡ t♦ t❤❡ ♣r❡s❡♥❝❡ ♦❢ ❛

♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ k ❛t ❛ ❞✐st❛♥❝❡ ξ′′ ❢r♦♠ i✳ ❚❤❡ ❝✉♠✉❧❛t✐✈❡ ❡✛❡❝t ♦❢ t❤❡ ♣♦❧②✲

♠❡r✐❝ ♣❛rt✐❝❧❡s k ✐s ♦❜t❛✐♥❡❞ ❜② ♠✉❧t✐♣❧②✐♥❣ t❤❡ tr✐♣❧❡t ❞❡♥s✐t② Tbbp(ξ + ξ′, ξ′′)

❜② t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ′′||/wd) ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′′✳

❚❤❡ r❡s✉❧t ✐s t❤❡♥ ♠✉❧t✐♣❧✐❡❞ ❜② t❤❡ ♠♦t✐❧✐t② ❦❡r♥❡❧ K(||ξ′||/wm)✱ ✐♥t❡❣r❛t❡❞

♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′ ❛♥❞ ♠✉❧t✐♣❧✐❡❞ ❜② t❤❡ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡ m2✳

t❤❡ ❢❛❝t♦r ✷ ❛❝❝♦✉♥ts ❢♦r ❛♥❛❧♦❣♦✉s ❡✈❡♥t t❤❛t ♠❛② ❜❡ ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ❝❡❧❧

j ✐♥ t❤❡ ♣❛✐r (i, j)✳

✻✳✷✳✷✳✷ ❉②♥❛♠✐❝ ♦❢ t❤❡ ♣♦❧②♠❡r✲♣♦❧②♠❡r ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥

❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs ♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ❞✐st❛♥❝❡

ξ ✐s ❣✐✈❡♥ ❜✉② t❤❡ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥✿

dCpp(ξ)

dt=

(

dCpp(ξ)

dt

)

production

+

(

dCpp(ξ)

dt

)

detachment

✭✻✳✶✻✮

❚❤❡ ✜rst t❡r♠ ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ ♣♦❧②♠❡r

♣r♦❞✉❝t✐♦♥ ❡✈❡♥ts ❛♥❞ t❤❡ s❡❝♦♥❞ t❡r♠ ❢♦r ♣♦❧②♠❡r ❞❡t❛❝❤♠❡♥t ❡✈❡♥ts ✳ P♦❧②♠❡r

♣r♦❞✉❝t✐♦♥ ❡✈❡♥ts ❝♦♥tr✐❜✉t❡ t♦ t❤❡ ❝r❡❛t✐♦♥ ♣♦s✐t✐✈❡❧② t♦ Cpp(ξ) ❛❝❝♦r❞✐♥❣ t♦ t❤❡

❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥✿

(

dCpp(ξ)

dt

)

production

= +2b2

K

(

||ξ′||

wb

)

Cbp(ξ + ξ′)dξ′ ✭✻✳✶✼✮

Page 109: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✾✻ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

• t❤❡ r✐❣❤t ❤❛♥❞✲s✐❞❡ ❛❝❝♦✉♥ts ❢♦r ♥❡✇ ♣❛✐rs ♦❢ ♣♦❧②♠❡rs t❤❛t ❛r❡ ❢♦r♠❡❞ ✇❤❡♥

t❤❡ ❜❛❝t❡r✐❛❧ ❝❡❧❧ i s✐t✉❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ + ξ′ ❢r♦♠ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ j

♣r♦❞✉❝❡s ❛ ♥❡✇ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ k ❛t ❛ ❞✐st❛♥❝❡ ξ′✳ ❚❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs (i, j)

✐s Cbp(ξ + ξ′) ❛♥❞ t❤❡ ♣r♦❜❛❜✐❧✐t② t❤❛t t❤❡ ♥❡✇❧② ❢♦r♠❡❞ ♣♦❧②♠❡r ♣❛rt✐❝❧❡s ✐s

❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ′ ❢r♦♠ t❤❡ ❝❡❧❧ i ✐s ❣✐✈❡♥ ❜② K(||ξ′||/wb)✳ ▼✉❧t✐♣❧②✐♥❣

t❤❡s❡ t✇♦ ❢❛❝t♦rs ✇✐t❤ t❤❡ ♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ r❛t❡ b2 ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧

♣♦ss✐❜❧❡ ❞✐st❛♥❝❡s ξ′ ❣✐✈❡s t❤❡ t❡r♠ ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡✳

❚❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ t❤❡ ❞❡t❛❝❤♠❡♥t ♦❢ ♣♦❧②♠❡r t♦ t❤❡ ❞②♥❛♠✐❝ ♦❢ Cpp(ξ) ✐s ❣✐✈❡♥

❜②✿

(

dCpp(ξ)

dt

)

detachment

= −2d2Cpp(ξ)

−2d′2Cpp(ξ)K

(

||ξ||

wd

)

−2d′2

K

(

||ξ′′||

wd

)

Tppp(ξ, ξ′′)dξ′′ ✭✻✳✶✽✮

• ❚❤❡ ✜rst t❡r♠ ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ tr❛♥s❧❛t❡s t❤❡ ❞❡str✉❝t✐♦♥ ♦❢ ♣❛✐r ♦❢

♣♦❧②♠❡r (i, j) ✐s ♦♥❡ ♦❢ t❤❡ ♣❛rt✐❝❧❡s i ♦r j ❞❡t❛❝❤✳

• ❚❤❡ s❡❝♦♥❞ t❡r♠ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❡✛❡❝t ♦❢ t❤❡ ♣❛rt✐❝❧❡ j ✐♥ t❤❡ ♣❛✐r (i, j) ♦♥

t❤❡ ❞❡t❛❝❤♠❡♥t r❛t❡ ♦❢ t❤❡ ♣❛rt✐❝❧❡ i✳ ❚❤✐s ✐s ♦❜t❛✐♥❡❞ ❜② ♠✉❧t✐♣❧②✐♥❣ t❤❡

❞❡♥s✐t② ♦❢ ♣❛✐rs Cpp(ξ) ❜② t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ||/wd)✳ ▼✉❧t✐♣❧②✐♥❣ ❜②

d′2 ❣✐✈❡s t❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ t❤✐s ♣r♦❝❡ss✳

• ❚❤❡ t❤✐r❞ t❡r♠ ❛❝❝♦✉♥ts ❢♦r ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s k t❤❛t ❛r❡ ♥❡✐❣❤❜♦rs ♦❢ ❛

♣❛rt✐❝❧❡ i ✐♥ t❤❡ ♣❛✐r (i, j)✳ ❚❤❡ ❞❡♥s✐t② ♦❢ ♣❛rt✐❝❧❡s ✐♥ t❤✐s ❝♦♥✜❣✉r❛t✐♦♥ ✐s

❣✐✈❡♥ ❜② Tppp(ξ, ξ′′)✳ ❲❤❡r❡ ξ′′ ✐s t❤❡ ❞✐st❛♥❝❡ ❜❡t✇❡❡♥ t❤❡ ♣❛rt✐❝❧❡s k ❛♥❞ i✳

❚❤✐s ❞❡♥s✐t② ✐s ✇❡✐❣❤t❡❞ ❜② t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ′′||/wd) ❛♥❞ ♠✉❧t✐♣❧✐❡❞

❜② t❤❡ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡✳ ■♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′′

❣✐✈❡s t❤❡ t❤✐r❞ t❡r♠✳

❚❤❡ ❢❛❝t♦r 2 ✐♥ t❤❡ r✐❣❤t ❤❛♥❞ s✐❞❡ ♦❢ ❡q✉❛t✐♦♥ ✻✳✶✽ ❛❝❝♦✉♥ts ❢♦r ❛♥❛❧♦❣♦✉s ❞❡t❛❝❤✲

♠❡♥t ❡✈❡♥ts t❤❛t ♠❛② ❜❡ ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ♣❛rt✐❝❧❡ j ✐♥ t❤❡ ♣❛✐r i, j✳

✻✳✷✳✷✳✸ ❉②♥❛♠✐❝ ♦❢ t❤❡ ❜❛❝t❡r✐❛✲♣♦❧②♠❡r ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥

❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ❜❛❝t❡r✐❛✲♣♦❧②♠❡r ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ Cbp(ξ) ✐s ♠♦r❡ ❝♦♠✲

♣❧❡①✳ ❆❧❧ ♣r♦❝❡ss❡s ❛✛❡❝t✐♥❣ t❤❡ ❜❛❝t❡r✐❛ ❛♥❞ t❤❡ ♣♦❧②♠❡r ❝♦♥tr✐❜✉t❡s t♦ t❤✐s ❞②✲

♥❛♠✐❝ ❛s ❝❛♥ ❜❡ s❤♦✇♥ ❢r♦♠ t❤❡ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥✿

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✻✳✷✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ✾✼

dCbp(ξ)

dt= +

(

dCbp(ξ)

dt

)

division

+

(

dCbp(ξ)

dt

)

production

+

(

dCbp(ξ)

dt

)

detachment bact

+

(

dCbp(ξ)

dt

)

detachment poly

+

(

dCbp(ξ)

dt

)

motility

✭✻✳✶✾✮

❚❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥ t♦ t❤❡ ❞②♥❛♠✐❝ ♦❢ Cbp(ξ) ✐s ❣✐✈❡♥ ❜②✿(

dCbp(ξ)

dt

)

division

= +b1

K

(

||ξ′||

wb

)

Cbp(ξ + ξ′)dξ′ ✭✻✳✷✵✮

• t❤❡ t❡r♠ ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❝❛s❡ ✇❤❡r❡ ❛ ♥❡✇ ♣❛✐r t❤❛t

❛ ❞❛✉❣❤t❡r ❝❡❧❧ k r❡s✉❧t❛♥t ❢r♦♠ t❤❡ ❞✐✈✐s✐♦♥ ♦❢ ❛ ♣❛r❡♥t ❝❡❧❧ i ❢♦r♠s ✇✐t❤ ❛

♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ j ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ+ξ′ ❢r♦♠ i✳ ❚❤❡ ♣❡r ❝❛♣✐t❛ ❜❛❝t❡r✐❛

❞✐✈✐s✐♦♥ r❛t❡ ✐s b1✱ t❤❡ ❞❡♥s✐t② ♦❢ (i, j) ♣❛✐rs ✐s Cbp(ξ+ξ′) ❛♥❞ t❤❡ s♣❛t✐❛❧ ❞❡♥s✐t②

♦❢ ❞❛✉❣❤t❡r ❝❡❧❧s ❛t ❞✐st❛♥❝❡ ξ′ ✐s K(||ξ′||/wb)✳ ▼✉❧t✐♣❧②✐♥❣ t❤❡s❡ ❢❛❝t♦rs ❛♥❞

✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′ ❣✐✈❡s t❤❡ t❡r♠ ♦♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡✳

❚❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ ♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ t♦ t❤❡ ❞②♥❛♠✐❝ ♦❢ Cbp(ξ) ✐s ❣✐✈❡♥ ❜②

t❤❡ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥✿

(

dCbp(ξ)

dt

)

production

= +b2NbK

(

||ξ||

wb

)

+b2

K

(

||ξ′||

wb

)

Cbb(ξ + ξ′)dξ′ ✭✻✳✷✶✮

• ❚❤❡ ✜rst t❡r♠ ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ❛❝❝♦✉♥ts ❢♦r ♥❡✇ ♣❛✐rs (k, j) ❢♦r♠❡❞ ❜② ❛

❜❛❝t❡r✐✉♠ k ❛♥❞ ❛ ♣r♦❞✉❝❡❞ ♣♦❧②♠❡r ♣❛rt✐❝❧❡ j ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ✳ ❚❤❡

♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ r❛t❡ ✐s b2Nb ❛♥❞ t❤❡ ❞❡♥s✐t② ♦❢ s❡❧❢✲♣r♦❞✉❝❡❞ ♣♦❧②♠❡r

♣❛rt✐❝❧❡s ❛t ❛ ❞✐st❛♥❝❡ ξ ❢r♦♠ ❛ ❢♦❝❛❧ ❜❛❝t❡r✐✉♠ i ✐s K(||ξ||/wb)✳ ▼✉❧t✐♣❧②✐♥❣

t❤❡s❡ ❢❛❝t♦rs ❣✐✈❡s t❤❡ ✜rst t❡r♠✳

• ■♥ t❤❡ s❡❝♦♥❞ t❡r♠ ✇❡ ❢♦❝✉s ♦♥ ♣❛✐rs (i, j) ❢♦r♠❡❞ ✇✐t❤ t✇♦ ❜❛❝t❡r✐❛ ❛t ❛

❞✐st❛♥❝❡ ξ + ξ′✳ ■❢ t❤❡ ❜❛❝t❡r✐❛ i ♣r♦❞✉❝❡s ❛ ♣♦❧②♠❡r ♣❛rt✐❝❧❡ k ❛t ❞✐st❛♥❝❡ ξ′

t❤❛♥ ❛ ♥❡✇ ♣❛✐r ❜❛❝t❡r✐❛ ♣♦❧②♠❡r (j, k) ✐s ❢♦r♠❡❞ ❛t ❞✐st❛♥❝❡ ξ✳ ❚❤❡ ❞❡♥s✐t② ♦❢

♣❛✐rs (i, j) ✐s Cbb(ξ+ξ′) ❛♥❞ t❤❡ ♣r♦❜❛❜✐❧✐t② t❤❛t t❤❡ ♣♦❧②♠❡r ♣❛rt✐❝❧❡ ♣r♦❞✉❝❡❞

❜② t❤❡ ❝❡❧❧ i ✐s ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ′ ✐s K(||ξ′||/wb)✳ ▼✉❧t✐♣❧②✐♥❣ t❤❡s❡ t✇♦

❢❛❝t♦rs ❜② t❤❡ ♣❡r ❝❛♣✐t❛ ♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ r❛t❡ ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧

❞✐st❛♥❝❡s ξ′ ❣✐✈❡s t❤❡ s❡❝♦♥❞ t❡r♠✳

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✾✽ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

❚❤❡ ❝♦♥tr✐❜✉t✐♦♥ ♦❢ ❜❛❝t❡r✐❛ ❛♥❞ ♣♦❧②♠❡r ❞❡t❛❝❤♠❡♥t ♣r♦❝❡ss❡s ✐s ❣✐✈❡♥ r❡s♣❡❝✲

t✐✈❡❧② ❜② t❤❡ t✇♦ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥s ✇❤✐❝❤ ❤❛✈❡ ❛ ❝♦♠♣❛r❛❜❧❡ str✉❝t✉r❡✿

(

dCbp(ξ)

dt

)

detachment bact

= −d1Cbp(ξ)

−d′1

K

(

||ξ′′||

wd

)

Tbpp(ξ, ξ′′)dξ′′

−d′1K

(

||ξ||

wd

)

Cbp(ξ) ✭✻✳✷✷✮

(

dCbp(ξ)

dt

)

detachment poly

= −d2Cbp(ξ)

−d′2

K

(

||ξ′′||

wd

)

Tbpp(ξ, ξ + ξ′′)dξ′′ ✭✻✳✷✸✮

❚❤❡ ✜rst t✇♦ t❡r♠s ♦❢ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ♦❢ ❜♦t❤ ❡q✉❛t✐♦♥s ❛r❡ ❝♦♠♣❛r❛❜❧❡✿

• t❤❡ ✜rst t❡r♠ t❛❦❡s ✐♥t♦ ❛❝❝♦✉♥t t❤❡ ❡✛❡❝t ♦❢ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞✲✐♥❞❡♣❡♥❞❡♥t ❞❡✲

t❛❝❤♠❡♥t ❡✈❡♥ts ♦❢ ❛ ❜❛❝t❡r✐✉♠ ✭❡q✉❛t✐♦♥ ✻✳✷✷✮ ♦r ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ✭❡q✉❛✲

t✐♦♥ ✻✳✷✸✮✳

• t❤❡ s❡❝♦♥❞ t❡r♠ t❛❦❡s ✐♥t♦ ❛❝❝♦✉♥t t❤❡ ❡✛❡❝t ♦❢ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ❞❡♣❡♥❞❡♥t

❞❡t❛❝❤♠❡♥t ♦❢ ❛ ❜❛❝t❡r✐✉♠ ✭❡q✉❛t✐♦♥ ✻✳✷✷✮ ♦r ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ✭❡q✉❛t✐♦♥

✻✳✷✸✮✳ ❋♦r t❤❡ ❝❛❧❝✉❧❛t✐♦♥ ♦❢ t❤✐s t❡r♠ tr✐♣❧❡ts ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❢♦r♠❡❞ ✇✐t❤ ❛

♣❛✐r ❜❛❝t❡r✐✉♠✲♣♦❧②♠❡r (i, j) ❛♥❞ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ k ♥❡❡❞ t♦ ❜❡ ❝♦♥s✐❞❡r❡❞✳

■♥ ❡q✉❛t✐♦♥ ✻✳✷✷ ✇❡ ❛❝❝♦✉♥t ❢♦r t❤❡ ❡✛❡❝t ♦❢ t❤❡ ♣♦❧②♠❡r k ♦♥ t❤❡ ❜❛❝t❡r✐✉♠

❞❡t❛❝❤♠❡♥t ❛♥❞ ✉s❡ t❤❡ ❞❡♥s✐t② ♦❢ tr✐♣❧❡t Tbpp(ξ, ξ′′) ✇❤✐❧❡ ✐♥ ❡q✉❛t✐♦♥ ✻✳✷✸ ✇❡

❛❝❝♦✉♥t ❢♦r t❤❡ ❡✛❡❝t ♦❢ t❤❡ ♣♦❧②♠❡r k ♦♥ t❤❡ ❞❡t❛❝❤♠❡♥t ♦❢ t❤❡ ♣♦❧②♠❡r✐❝

♣❛rt✐❝❧❡ j ✐♥ t❤❡ ♣❛✐r ✭✐✱❥✮ ❛♥❞ ✉s❡ t❤❡ ❞❡♥s✐t② ♦❢ tr✐♣❧❡t Tbpp(ξ, ξ + ξ′′)✳

• t❤❡ t❤✐r❞ t❡r♠ ✐♥ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ♦❢ ❡q✉❛t✐♦♥ ✻✳✷✷ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❡✛❡❝t ♦❢

t❤❡ ♣♦❧②♠❡r ♣❛rt✐❝❧❡ j ✐♥ t❤❡ ❜❛❝t❡r✐✉♠✲♣♦❧②♠❡r ♣❛✐r (i, j) ♦♥ t❤❡ ❞❡t❛❝❤♠❡♥t

r❛t❡ ♦❢ t❤❡ ❜❛❝t❡r✐✉♠ i✳

❋✐♥❛❧❧② t❤❡ ♠♦t✐❧✐t② ♣r♦❝❡ss ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❛❧s♦ ❝♦♥tr✐❜✉t❡s t♦ t❤❡ ❞②♥❛♠✐❝ ♦❢

t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ Cbp(ξ) ❛❝❝♦r❞✐♥❣ t♦ t❤❡ ❢♦❧❧♦✇✐♥❣ ❡q✉❛t✐♦♥✿

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✻✳✷✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ✾✾

(

dCbp(ξ)

dt

)

motility

= −m1Cbp(ξ)

+m1

K

(

||ξ′||

wm

)

Cbp(ξ + ξ′)dξ′

+m2

K

(

||ξ′′||

wd

)

Tbpp(ξ, ξ′′)dξ′′

−m2

∫ ∫

K

(

||ξ′′||

wd

)

K

(

||ξ′||

wm

)

Tbpp(ξ + ξ′, ξ′′)dξ′dξ′′

+m2Cbp(ξ)K

(

||ξ||

wd

)

−m2

K

(

||ξ′||

wm

)

K

(

||ξ + ξ′||

wd

)

Cbp(ξ + ξ′)dξ′ ✭✻✳✷✹✮

• ❲❤❡♥ t❤❡ ❜❛❝t❡r✐✉♠ i✱ ✐♥ ❛ ❜❛❝t❡r✐✉♠✲♣♦❧②♠❡r ♣❛✐r (i, j) ❛t ❞✐st❛♥❝❡ ξ✱ ♠♦✈❡s✱

t❤❡ ♦r✐❣✐♥❛❧ ♣❛✐r (i, j) ✐s ❞❡str♦②❡❞✳ ❚❤✐s ✐s ❛❝❝♦✉♥t❡❞ ❢♦r ✇✐t❤ t❤❡ ✜rst t❡r♠✳

• ❖♥ t❤❡ ♦t❤❡r ❤❛♥❞✱ ✇❤❡♥ ❛ ♥❡✇ ♣❛✐r (i, j) ❛t ❞✐st❛♥❝❡ ξ ✐s ❢♦r♠❡❞ ✐s t❤❡

❜❛❝t❡r✐✉♠ ♦r✐❣✐♥❛❧❧② ❛t ❛ ❞✐st❛♥❝❡ ξ + ξ′ ❢r♦♠ t❤❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ j ♠♦✈❡s

✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ′✳ ❚❤✐s ♣r♦❝❡ss ✐s ❝♦♥s✐❞❡r❡❞ ❜② t❤❡ s❡❝♦♥❞ t❡r♠✳

• ❚❤❡ t❤✐r❞ t❡r♠ ❝♦rr❡❝ts t❤❡ ✜rst t❡r♠ ❜② ❛❝❝♦✉♥t✐♥❣ ❢♦r t❤❡ ♣♦ss✐❜❧❡ ♣r❡s❡♥❝❡

♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ✐♥ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡ ❜❛❝t❡r✐✉♠ ✐♥ t❤❡ ❜❛❝t❡r✐✉♠✲

♣♦❧②♠❡r ♣❛✐r (i, j) ♦r✐❣✐♥❛❧❧② ❛t ❛ ❞✐st❛♥❝❡ ξ✳ ❚❤❡ ♠♦t✐❧✐t② ♦❢ i ✐♥ t❤❡ ♣❛✐r (i, j)

✐s r❡❞✉❝❡❞ ❜② t❤❡ ♣r❡s❡♥❝❡ ♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ k ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ′′ ❢r♦♠

i✳ ❚❤❡ ❞❡♥s✐t② tr✐♣❧❡t ❢♦r♠❡❞ ✇✐t❤ t❤❡ ♣❛✐r (i, j) s❡♣❛r❛t❡❞ ✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ

❛♥❞ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ❛t ❛ ❞✐st❛♥❝❡ ξ′′ ❢r♦♠ i ✐s Tbpp(ξ, ξ′′)✳ ▼✉❧t✐♣❧②✐♥❣ t❤✐s

❞❡♥s✐t② ❜② t❤❡ ♣❡r ❝❛♣✐t❛ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡ m2✱ ✇❡✐❣❤t✐♥❣ ❜②

t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ′′||/wd) ❛♥❞ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′′ ❣✐✈❡s

t❤❡ t❤✐r❞ t❡r♠✳

• ❚❤❡ ❢♦✉rt❤ t❡r♥ ❝♦rr❡❝ts t❤❡ s❡❝♦♥❞ t❡r♠ ❜② ❛❝❝♦✉♥t✐♥❣ ❢♦r ♠♦t✐❧✐t② r❡❞✉❝t✐♦♥

♦❢ t❤❡ ❜❛❝t❡r✐✉♠ i ♦r✐❣✐♥❛❧❧② ❛t ❛ ❞✐st❛♥❝❡ ξ + ξ′ ❢r♦♠ t❤❡ ❛ ♣♦❧②♠❡r✐❝ ♣❛r✲

t✐❝❧❡ j ❞✉❡ t♦ t❤❡ ♣r❡s❡♥❝❡ ♦❢ ❛ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ k ❛t ❛ ❞✐st❛♥❝❡ ξ′′ ❢r♦♠ i✳

❚❤❡ ❝✉♠✉❧❛t✐✈❡ ❡✛❡❝t ♦❢ t❤❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s k ✐s ♦❜t❛✐♥❡❞ ❜② ♠✉❧t✐♣❧②✐♥❣

t❤❡ tr✐♣❧❡t ❞❡♥s✐t② Tbpp(ξ + ξ′, ξ′′) ❜② t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ U(||ξ′′||/wd) ❛♥❞

✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′′✳ ❚❤❡ r❡s✉❧t ✐s t❤❡♥ ♠✉❧t✐♣❧✐❡❞ ❜② t❤❡ ♠♦t✐❧✲

✐t② ❦❡r♥❡❧ K(||ξ′||/wm)✱ ✐♥t❡❣r❛t❡❞ ♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′ ❛♥❞ ♠✉❧t✐♣❧✐❡❞ ❜② t❤❡

❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡ m2✳

• ❚❤❡ ✜❢t❤ t❡r♠ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❡✛❡❝t ♦❢ t❤❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ✐♥ t❤❡

❜❛❝t❡r✐✉♠✲♣♦❧②♠❡r ♣❛✐r (i, j) ❛t ❛ ❞✐st❛♥❝❡ ξ ♦♥ t❤❡ ♠♦t✐❧✐t② ♦❢ i✳ ❚❤❡ ❞❡♥s✐t②

♦❢ ♣❛✐rs (i, j) ✐s Cbp(ξ)✳ ❲❡✐❣❤t❡❞ ❜② t❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ K(||ξ||/wd) ❛♥❞

♠✉❧t✐♣❧✐❡❞ ❜② t❤❡ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ♣❡r ❝❛♣✐t❛ ♠♦t✐❧✐t② r❛t❡ m2 ②✐❡❧❞s t❤❡

✜❢t❤ t❡r♠

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✶✵✵ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

• ❚❤❡ s✐①t❤ t❡r♠ ❝♦rr❡❝ts t❤❡ s❡❝♦♥❞ t❡r♠ ✐♥ ✇❤✐❝❤ ❛ ❜❛❝t❡r✐✉♠ ♣♦❧②♠❡r ♣❛✐r

♦r✐❣✐♥❛❧❧② ❛t ❛ ❞✐st❛♥❝❡ ξ + ξ′ ②✐❡❧❞s ❛ ♥❡✇ ♣❛✐r ❛t ❛ ❞✐st❛♥❝❡ ξ ❛❢t❡r t❤❡

❜❛❝t❡r✐✉♠ ❤❛s ♠♦✈❡❞ ✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ′✳ ❚❤❡ s✐①t❤ t❡r♠ ❛❝❝♦✉♥t ❢♦r t❤❡ ❡✛❡❝t

♦❢ t❤❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡ ✐♥ t❤✐s ♣❛✐r ♦♥ t❤❡ ♠♦t✐❧✐t② ♦❢ t❤❡ ❜❛❝t❡r✐✉♠✳ ❚❤❡

❞❡♥s✐t② ♦❢ t❤❡ ♦r✐❣✐♥❛❧ ♣❛✐rs ✐s Cbp(ξ + ξ) t❤❛t ✇❡ ✇❡✐❣❤t ❜② t❤❡ ✐♥t❡r❛❝t✐♦♥

❦❡r♥❡❧ K(||ξ + ξ′||/wd)✳ ▼✉❧t✐♣❧②✐♥❣ ❜② K(||ξ′||/wm) ✇❤✐❝❤ r❡♣r❡s❡♥ts t❤❡

♣r♦❜❛❜✐❧✐t② t♦ ♠♦✈❡ ✇✐t❤ ❛ ❞✐st❛♥❝❡ ξ′ ❛♥❞ t❤❡ ♣❡r ❝❛♣✐t❛ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t

♠♦t✐❧✐t② r❛t❡s t❤❛♥ ✐♥t❡❣r❛t✐♥❣ ♦✈❡r ❛❧❧ ❞✐st❛♥❝❡s ξ′ ②✐❡❧❞s t❤❡ s✐①t❤ t❡r♠✳

✻✳✷✳✸ ❈❧♦s✉r❡ ♦❢ t❤❡ ♠♦♠❡♥t ❤✐❡r❛r❝❤②

❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✜rst ♠♦♠❡♥t ✐♥✈♦❧✈❡s s❡❝♦♥❞ ♠♦♠❡♥t t❡r♠s ❛♥❞ t❤❡ ❞②♥❛♠✐❝

♦❢ t❤❡ s❡❝♦♥❞ ♠♦♠❡♥t ✐♥✈♦❧✈❡s t❤❡ t❤✐r❞ ♠♦♠❡♥t t❡r♠s✳ ❚♦ tr✉♥❝❛t❡ t❤❡ ❤✐❡r❛r❝❤②

♦❢ t❤❡ ♠♦♠❡♥t ✇❡ s✉♣♣♦s❡ t❤❛t t❤❡ ♣♦s✐t✐♦♥ ♦❢ tr✐♣❧❡t ♣❛rt✐❝❧❡s ❛r❡ ♥♦t ❝♦rr❡❧❛t❡❞

❛♥❞ ❝❛♥ ❜❡ ❡①♣r❡ss❡❞ ❛s t❤❡ ♣r♦❞✉❝t ♦❢ t❤❡ s❡❝♦♥❞ ♠♦♠❡♥t t❡r♠s✳ ❚❤✐s ②✐❡❧❞s t❤❡

❢♦❧❧♦✇✐♥❣ ❝❧♦s✉r❡ ❡①♣r❡ss✐♦♥s✿

Tppp(ξ, ξ′′) =

Cpp(ξ)Cpp(ξ′′)

Np✭✻✳✷✺✮

Tbpp(ξ, ξ′′) =

Cbp(ξ)Cbp(ξ′′)

Nb✭✻✳✷✻✮

Tbbp(ξ, ξ′′) =

Cbb(ξ)Cbp(ξ′′)

Nb✭✻✳✷✼✮

✻✳✷✳✹ ❙♦❧✈✐♥❣ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧

❚❤❡ st❛t❡ ✈❛r✐❛❜❧❡s ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛r❡ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t✐❡s ♦❢ ❜❛❝t❡r✐❛ (Nb)

❛♥❞ ♣♦❧②♠❡r (Np) ❛♥❞ t❤❡ t❤r❡❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s Cbb(ξ)✱ Cpp(ξ) ❛♥❞ Cbp(ξ)✳

❚❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ❛r❡ ❞✐s❝r❡t✐③❡❞ ✇✐t❤ r❡❣❛r❞s t♦ s♣❛❝❡ ✇✐t❤ s♣❛t✐❛❧ r❡s✲

♦❧✉t✐♦♥ dξ = (dξ1, dξ2) ❛♥❞ t❤❡② ❛r❡ tr❛♥s❢♦r♠❡❞ ✐♥t♦ t❤r❡❡ ♠❛tr✐❝❡s✳ ❲❡ ❞✐s❝r❡t✐③❡

t✐♠❡ ❞❡r✐✈❛t✐✈❡s ❛❝❝♦r❞✐♥❣ t♦ ❛♥ ❊✉❧❡r ❡①♣❧✐❝✐t s❝❤❡♠❡ ❛♥❞ ✇❡ ✉s❡ ❛ ✜①❡❞ t✐♠❡ st❡♣

∆t = 0.1✳

✻✳✸ ❘❡s✉❧ts ❛♥❞ ❞✐s❝✉ss✐♦♥

■♥ t❤✐s s❡❝t✐♦♥ ✇❡ ❝♦♠♣❛r❡ t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❆❧❧ ♣❛r❛♠❡t❡rs t❛❦❡

t❤❡ ✈❛❧✉❡s ❧✐st❡❞ ✐♥ t❛❜❧❡ ✻✳✶ ✉♥❧❡ss ♦t❤❡r✇✐s❡ st❛t❡❞✳ ■♥ t❤❡ ✜rst ♣❛rt ✇❡ t✉r♥ ♦✛

❛❧❧ t❤❡ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ♣r♦❝❡ss❡s ❛♥❞ ❛ss❡ss ❤♦✇ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t②

❛✛❡❝ts t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥✳ ❲❡ s❤♦✇ t❤❛t ♠♦t✐❧✐t② ♣r♦♠♦t❡s t❤❡ ❞✐s♣❡rs✐♦♥ ♦❢ t❤❡

❜❛❝t❡r✐❛ ❛♥❞ ♣r❡✈❡♥ts ❝♦❧♦♥② ❢♦r♠❛t✐♦♥✳ ■♥ t❤❡ s❡❝♦♥❞ ♣❛rt ✇❡ t✉r♥ ♦♥ t❤❡ ♠♦t✐❧✐t②

❞❡♣❡♥❞❡♥❝❡ ♦♥ t❤❡ ❧♦❝❛❧ ♣♦❧②♠❡r ❞❡♥s✐t② ❛♥❞ ❝♦♠♣❛r❡ t❤❡ ♣❛tt❡r♥ t♦ t❤❡ ♣r❡✈✐♦✉s❧②

♦❜t❛✐♥❡❞ ♦♥❡s✳ ❲❡ s❤♦✇ t❤❛t t❤❡ r❡❞✉❝t✐♦♥ ♦❢ ♠♦t✐❧✐t② ❞✉❡ t♦ t❤❡ ♣r♦❞✉❝❡❞ ♣♦❧②♠❡r

♣r♦♠♦t❡s ❝♦❧♦♥② ❢♦r♠❛t✐♦♥✳ ❋✐♥❛❧❧②✱ ✇❡ t✉r♥ ♦♥ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t

♣r♦❝❡ss❡s✳ ❚❤❡ ❞❡t❛❝❤♠❡♥t r❛t❡ ✐♥❝r❡❛s❡s ✇✐t❤ t❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t②

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✻✳✸✳ ❘❡s✉❧ts ❛♥❞ ❞✐s❝✉ss✐♦♥ ✶✵✶

P❛r❛♠❡t❡rs ❉❡s❝r✐♣t✐♦♥ ❱❛❧✉❡

L ❉♦♠❛✐♥ s✐③❡ 101× 101

∆L ❙♣❛t✐❛❧ ❞✐s❝r❡t✐③❛t✐♦♥ 1

b1 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥ r❛t❡ 0.1

b2 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ r❛t❡ 0.1

d1 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❜❛❝t❡r✐❛ ❞❡t❛❝❤♠❡♥t r❛t❡ 0.1

d2 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♣♦❧②♠❡r ❞❡t❛❝❤♠❡♥t r❛t❡ 0.1

d′1 ❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❜❛❝t❡r✐❛ ❞❡t❛❝❤♠❡♥t r❛t❡ 0.0

d′2 ❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣♦❧②♠❡r ❞❡t❛❝❤♠❡♥t r❛t❡ 0.0

m1 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡ 1.0

m2 ❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡ 2.0

wb ❯♥✐❢♦r♠ ❞✐✈✐s✐♦♥ ❛♥❞ ♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ ❦❡r♥❡❧ s✐❞❡ 5

wd ❯♥✐❢♦r♠ ■♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ s✐❞❡ 5

wm ❯♥✐❢♦r♠ ♠♦t✐❧✐t② ❦❡r♥❡❧ s✐❞❡ 5

❚❛❜❧❡ ✻✳✶✿ ▼♦❞❡❧ ♣❛r❛♠❡t❡rs

♦❢ ♣♦❧②♠❡r✳ ❲❡ ✐♥✈❡st✐❣❛t❡ ❤♦✇ t❤✐s ♣r♦❝❡ss ❛✛❡❝t t❤❡ ❛❣❣r❡❣❛t❡❞ ♣❛tt❡r♥ ❢♦r♠❡❞

❜② ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t②✳ ❆❧❧ ❛❧♦♥❣ t❤✐s s❡❝t✐♦♥ ✇❡ ❝♦♠♣❛r❡ t❤❡ s✐♠✉❧❛t✐♦♥

♦❢ t❤❡ ■❇▼ ✇✐t❤ t❤❡ r❡s✉❧ts ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛♥❞ ❛ss❡ss t❤❡ ✈❛❧✐❞✐t② ♦❢ t❤❡

❛♣♣r♦①✐♠❛t✐♦♥ ♠❛❞❡ ✐♥ t❤❡ ♠♦♠❡♥t ❛♣♣r♦❛❝❤✳

❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦❞❡❧

■♥ t❤❡ ❛❜s❡♥❝❡ ♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣r♦❝❡ss❡s (m2 = 0✱ d′1 = 0✱ d′2 = 0) t❤❡

s♣❛t✐❛❧ ♣❛tt❡r♥ ❤❛s ♥♦ ❡✛❡❝t ♦♥ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t✐❡s ♦❢ ❜❛❝t❡r✐❛ ❛♥❞ ♣♦❧②♠❡r✳ ❋♦r

❛ s②st❡♠ ❢♦r♠❡❞ ✇✐t❤ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛ (m1 = 0) s♣❛t✐❛❧ ♣❛tt❡r♥ ❢♦r♠s ❛s ❛ r❡s✉❧t

♦❢ t❤❡ s❤♦rt✲r❛♥❣❡ ❞✐s♣❡rs✐♦♥ ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧s✳ ❋✐❣✉r❡ ✻✳✶ s❤♦✇s t✇♦ s♥❛♣s❤♦ts

♦❢ t❤❡ st❛t❡ ♦❢ t❤❡ s②st❡♠ ❢♦r t❤❡ ❝❛s❡s ♦❢ s❤♦rt✲r❛♥❣❡ (wb/L ∼ 0.05) ❛♥❞ ❧♦♥❣✲r❛♥❣❡

❞✐s♣❡rs✐♦♥ (wb/L ∼ 0.1) ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧s ✭L ✐s t❤❡ ❞♦♠❛✐♥ s✐③❡✮✳ ❚❤❡ ❢♦r♠❛t✐♦♥

♦❢ ❝♦❧♦♥✐❡s ✐s ❧❡ss ♠❛r❦❡❞ ❢♦r ❧❛r❣❡r ❞❛✉❣❤t❡r ❝❡❧❧s ❞✐s♣❡rs✐♦♥✳ ❚❤✐s r❡s✉❧t ✐s ✇❡❧❧

❝❛♣t✉r❡❞ ❜② t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ❢✉♥❝t✐♦♥ ❛s ❝❛♥ ❜❡ s❡❡♥ ✐♥ ✜❣✉r❡ ✻✳✷✳ ❋♦r

❧♦✇ ❞✐s♣❡rs✐♦♥ ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧s✱ t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs ♦❢ ❜❛❝t❡r✐❛ ✐♥❝r❡❛s❡s ❛t

s❤♦rt ❞✐st❛♥❝❡s s✉❣❣❡st✐♥❣ t❤❡ ❡①✐st❡♥❝❡ ♦❢ ❛ ❜❛❝t❡r✐❛✲❜❛❝t❡r✐❛ ❛❣❣r❡❣❛t✐♦♥ ❛t t❤❡s❡

❞✐st❛♥❝❡s✳ ▲❛r❣❡ ❞✐s♣❡rs✐♦♥ r❛♥❣❡ ②✐❡❧❞s ♣❛✐rs ❞❡♥s✐t② ❢✉♥❝t✐♦♥ t❤❛t t❛❦❡s ✈❛❧✉❡s ❝❧♦s❡

t♦ ✶✱ ✐♥❞✐❝❛t✐♥❣ ❛ ✉♥✐❢♦r♠ ♣❛tt❡r♥✳ ❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❝❛♣t✉r❡s ✇❡❧❧ t❤❡ ❞②♥❛♠✐❝

♦❢ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✳

◆♦✇ ❤♦✇ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② ❛✛❡❝ts t❤❡ ❛❣❣r❡❣❛t❡❞ ♣❛tt❡r♥

②✐❡❧❞❡❞ ✐♥ t❤❡ ❝❛s❡ ♦❢ s❤♦rt r❛♥❣❡ ❞✐s♣❡rs✐♦♥❄ ❋✐❣✉r❡ ✻✳✸ s❤♦✇s s♥❛♣s❤♦ts ♦❢ t❤❡

s✐♠✉❧❛t❡❞ s②st❡♠ ✇❤❡♥ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② ♦❢ t❤❡ ❜❛❝t❡r✐❛ ✐s ❛❞❞❡❞✳ ❚❤❡

♠♦t✐❧✐t② r❛♥❣❡ ✐s ✈❛r✐❡❞ ❜② ✈❛r②✐♥❣ t❤❡ s✐③❡ wm ♦❢ t❤❡ ♠♦t✐❧✐t② ❦❡r♥❡❧✳ ■♥❝r❡❛s✐♥❣ t❤❡

♠♦t✐❧✐t② r❛♥❣❡ ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❞✐s♣❡rs❡ ❞❛✉❣❤t❡r ❝❡❧❧s ❛♥❞ t❤❡✐r ♣❛r❡♥ts ♣r❡✈❡♥t✐♥❣

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✶✵✷ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

✭❛✮ wb = 5

✭❜✮ wb = 11

❋✐❣✉r❡ ✻✳✶✿ ■❇▼ s♥❛♣s❤♦ts ♦❢ t❤❡ st❛t❡ ♦❢ t❤❡ s②st❡♠ ❛t t✐♠❡ t = 100 ❢♦r t❤❡

❝❛s❡ ♦❢ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛ m1 = 0.0✳ (a) s❤♦rt✲r❛♥❣❡ ❞✐s♣❡rs✐♦♥✱ (b) ❧♦♥❣✲r❛♥❣❡

❞✐s♣❡rs✐♦♥✳ ❚❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ♦t❤❡r ♣❛r❛♠❡t❡rs ❛r❡ b1 = d1 = 0.1✱ b2 = d2 = 0.1✱

d′1 = d′2 = m2 = 0.0 ✭♥♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣r♦❝❡ss❡s✮

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✻✳✸✳ ❘❡s✉❧ts ❛♥❞ ❞✐s❝✉ss✐♦♥ ✶✵✸

✭❛✮ wb = 5

✭❜✮ wb = 11

❋✐❣✉r❡ ✻✳✷✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s ♦❜t❛✐♥❡❞ ❜② t❤❡

■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛t t✐♠❡ t = 100 ❢♦r t❤❡ ❝❛s❡ ♦❢ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛

m1 = 0.0✳ (a) s❤♦rt✲r❛♥❣❡ ❞✐s♣❡rs✐♦♥✱ (b) ❧♦♥❣✲r❛♥❣❡ ❞✐s♣❡rs✐♦♥✳ ❚❤❡ ✈❛❧✉❡ ♦❢ t❤❡

♦t❤❡r ♣❛r❛♠❡t❡rs ❛r❡ b1 = d1 = 0.1✱ b2 = d2 = 0.1 ✭♥♦ ♣♦❧②♠❡r✮✱ d′1 = d′2 = m2 = 0.0

✭♥♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣r♦❝❡ss❡s✮

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✶✵✹ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

✭❛✮ sm = 3

✭❜✮ sm = 15

❋✐❣✉r❡ ✻✳✸✿ ■❇▼ s♥❛♣s❤♦ts ♦❢ t❤❡ st❛t❡ ♦❢ t❤❡ s②st❡♠ ❛t t✐♠❡ t = 150 ❢♦r t❤❡ ❝❛s❡

♦❢ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦t✐❧❡ ❜❛❝t❡r✐❛ m1 = 0.0✳ (a) s❤♦rt✲r❛♥❣❡ ♠♦t✐❧✐t②✱ (b) ❧♦♥❣✲

r❛♥❣❡ ♠♦t✐❧✐t②✳ ❚❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ♦t❤❡r ♣❛r❛♠❡t❡rs ❛r❡ b1 = d1 = 0.1✱ b2 = d2 = 0.1✱

d′1 = d′2 = m2 = 0.0 ✭♥♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣r♦❝❡ss❡s✮ ❛♥❞ wb = 5

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✻✳✸✳ ❘❡s✉❧ts ❛♥❞ ❞✐s❝✉ss✐♦♥ ✶✵✺

t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s✳ ■♥ ❡ss❡♥❝❡✱ t❤❡ ♠♦t✐❧✐t② ❛❝ts ❛s t❤❡ ❞✐s♣❡rs❛❧ ❦❡r♥❡❧ ❛♥❞

t❡♥❞ t♦ ♠✐① t❤❡ ❜❛❝t❡r✐❛ ②✐❡❧❞✐♥❣ ✉♥✐❢♦r♠ ♣❛tt❡r♥s✳ ❚❤✐s ✐s ❛❧s♦ ❞❡♠♦♥str❛t❡❞ ❜②

t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✐♥ ✜❣✉r❡ ✻✳✹✳ ❚❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✐♥ t❤❡

■❇▼ ❛♥❞ ♠♦♠❡♥t ♠♦❞❡❧s t❛❦❡ ✈❛❧✉❡s ❝❧♦s❡ t♦ ✶ ❢♦r ❧♦♥❣✲r❛♥❣❡ ♠♦t✐❧✐t② ✐♥❞✐❝❛t✐♥❣

❛ ✉♥✐❢♦r♠ s♣❛t✐❛❧ ♣❛tt❡r♥✳ ❲❡ s❤♦✇ ✐♥ t❤❡ ♥❡①t s❡❝t✐♦♥ t❤❛t ❧♦♥❣✲r❛♥❣❡ ♠♦t✐❧✐t②

♣❧❛②s t❤❡ ✐♥✈❡rs❡ r♦❧❡ ❛♥❞ ♣r♦♠♦t❡s ❛❣❣r❡❣❛t❡❞ ♣❛tt❡r♥s ❢♦r♠❛t✐♦♥ ✐♥ t❤❡ ❝❛s❡ ♦❢

❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t②

❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t②

■♥ t❤❡ ■❇▼✱ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② ♣r♦❝❡ss ✐s ❞❡s❝r✐❜❡❞ ❜② ❡q✉❛t✐♦♥ ✻✳✼✳

❚❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡ t❤❛t ❛ ❜❛❝t❡r✐✉♠ ♠♦✈❡s t♦ ❛♥② ♦t❤❡r ♣♦s✐t✐♦♥

✇✐t❤✐♥ t❤❡ ❞♦♠❛✐♥ ✐s ❣✐✈❡♥ ❜② m1 −m2ploc(x) ✇❤❡r❡ ploc(x) ✐s t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢

♣♦❧②♠❡r ♣❡r❝❡✐✈❡❞ ❜② t❤❡ ❜❛❝t❡r✐✉♠ ✐♥ ❧♦❝❛t✐♦♥ x✳ ❚❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t②

♦❢ ♣♦❧②♠❡r ✐s ♥♦t ❜♦✉♥❞❡❞ ❛s ❛ ❜❛❝t❡r✐✉♠ ❝❛♥ ❤②♣♦t❤❡t✐❝❛❧❧② ❤❛✈❡ ❛♥② ♥✉♠❜❡r ♦❢

♥❡✐❣❤❜♦r✐♥❣ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s✳ ■♥ ♦r❞❡r t♦ ❛✈♦✐❞ ♥❡❣❛t✐✈❡ ♣r♦❜❛❜✐❧✐t✐❡s ✇❡ ✜① ❛

t❤r❡s❤♦❧❞ ❢♦r t❤❡ ❧♦❝❛❧ ❞❡♥s✐t✐❡s ♦❢ ♣♦❧②♠❡r ❛❜♦✈❡ ✇❤✐❝❤ t❤❡ ♠♦t✐❧✐t② ♣r♦❜❛❜✐❧✐t②

✐s s❡t t♦ ③❡r♦✳ ❚❤❡ t❤r❡s❤♦❧❞ ✈❛❧✉❡ ❝♦rr❡s♣♦♥❞s t♦ m1/m2✳ ❲❤✐❧❡ ✐♥ t❤❡ ■❇▼ t❤❡

❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ♣❡r❝❡✐✈❡❞ ❜② ❛♥ ✐♥❞✐✈✐❞✉❛❧ ✢✉❝t✉❛t❡s ❞✉❡ t♦ t❤❡ ❞✐✛❡r❡♥t

st♦❝❤❛st✐❝ ♣r♦❝❡ss❡s✱ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ r❡❧✐❡s ♦♥ t❤❡ ❛✈❡r❛❣❡ ✈❛❧✉❡

♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ✇❤✐❝❤ ✐s✱ ❢♦r t❤❡ ♣❛r❛♠❡t❡rs ✉s❡❞ ✐♥ t❤✐s ❝❤❛♣t❡r✱

❛❧✇❛②s ❜❡❧♦✇ t❤❡ t❤r❡s❤♦❧❞ ✈❛❧✉❡ m1/m2✳

❋✐❣✉r❡ ✻✳✺ s❤♦✇s s♥❛♣s❤♦ts ♦❢ t❤❡ st❛t❡ ♦❢ t❤❡ s②st❡♠ ❢♦r ❞✐✛❡r❡♥t ✈❛❧✉❡s ♦❢ m2✳

■♥ t❤❡ ■❇▼✱ ✐♥❝r❡❛s✐♥❣ t❤❡ ✈❛❧✉❡ ♦❢ m2 ♣r♦♠♦t❡s t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s ❞✉❡

t♦ t❤❡ ❞❡❝r❡❛s❡ ♦❢ t❤❡ ✐♠♠♦❜✐❧✐③❛t✐♦♥ t❤r❡s❤♦❧❞✳ ❚❤✐s ❝❛♥ ❛❧s♦ ❜❡ ♦❜s❡r✈❡❞ ❢r♦♠

✜❣✉r❡ ✻✳✻ s❤♦✇✐♥❣ t❤❡ r❛❞✐❛❧ ♣❛✐rs ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✭❛t t✐♠❡ t = 400✮ s✐♠✉❧❛t❡❞

✇✐t❤ t❤❡ ■❇▼ ❛♥❞ ✇✐t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❚❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ♣❡❛❦❡❞ ❛t

s❤♦rt ❞✐st❛♥❝❡ ✇✐t❤ t❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ ✈❛❧✉❡ ♦❢ m2✳ ❙✉r♣r✐s✐♥❣❧②✱ ❝♦♠♣❛r✐s♦♥ ✇✐t❤

t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ s❤♦✇s t❤❛t t❤❡ ❧❛t❡r ❢❛✐❧ ✐♥ ❝❛♣t✉r✐♥❣ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s

✭✜❣✉r❡ ✻✳✻✭❜✮✮✳ ❚❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ②✐❡❧❞❡❞ ❜② t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ r❡♠❛✐♥s

❝❧♦s❡ t♦ ✶ ✐♥❞✐❝❛t✐♥❣ ❛ ✉♥✐❢♦r♠ ♣❛tt❡r♥✳ ❚♦ ❡①♣❧❛✐♥ t❤✐s ❞✐✛❡r❡♥❝❡ ✇❡ ❡①tr❛❝t❡❞ t❤❡

t✐♠❡ ❝♦✉rs❡ ♦❢ t❤❡ ❧♦❝❛❧ ♣♦❧②♠❡r ❞❡♥s✐t✐❡s ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛ ✐♥ t❤❡ ■❇▼

❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❚❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛ ✐♥ t❤❡ ■❇▼

❞✐✛❡r ❢r♦♠ ❛♥ ✐♥❞✐✈✐❞✉❛❧ t♦ ❛♥♦t❤❡r ❞❡♣❡♥❞✐♥❣ ♦♥ t❤❡ ❧♦❝❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧

❛♥❞ ✐ts ♥❡✐❣❤❜♦r❤♦♦❞✳ ❆t ❡❛❝❤ t✐♠❡ st❡♣ ✇❡ ❝❛❧❝✉❧❛t❡ t❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧ ❞❡♥s✐t②

♦❢ ♣♦❧②♠❡r ❛♥❞ t❤❡ ♠❛①✐♠✉♠ ✈❛❧✉❡ ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛✳ ■♥ t❤❡ ♠♦♠❡♥t

♠♦❞❡❧✱ ♦♥❧② t❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧ ♣♦❧②♠❡r✐❝ ❞❡♥s✐t② ✐s ❝♦♥s✐❞❡r❡❞ ✐♥ t❤❡ ♠♦❞❡❧ ❛♥❞ ✐s

❣✐✈❡♥ ❜②✿

ploc =

K

(

||ξ||

wd

)

Cbp(ξ)dξ ✭✻✳✷✽✮

❋✐❣✉r❡ ✻✳✼ ❝♦♠♣❛r❡s t❤❡ ❛✈❡r❛❣❡ ❛♥❞ ♠❛①✐♠✉♠ ✈❛❧✉❡s ♦❢ t❤❡ ❧♦❝❛❧ ♣♦❧②♠❡r ❞❡♥✲

s✐t② ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐♥ t❤❡ ■❇▼ ✇✐t❤ t❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢

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✶✵✻ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

✭❛✮ sm = 3

✭❜✮ sm = 151

❋✐❣✉r❡ ✻✳✹✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s ♦❜t❛✐♥❡❞ ❜② t❤❡ ■❇▼

❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛t t✐♠❡ t = 150 ❢♦r t❤❡ ❝❛s❡ ♦❢ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ m1 = 1.0 (a)

s❤♦rt✲r❛♥❣❡ ♠♦t✐❧✐t②✱ (b) ❧♦♥❣✲r❛♥❣❡ ♠♦t✐❧✐t②✳ ❚❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ♦t❤❡r ♣❛r❛♠❡t❡rs ❛r❡

b1 = d1 = 0.1✱ b2 = d2 = 0.1✱ d′1 = d′2 = m2 = 0.0 ✭♥♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣r♦❝❡ss❡s✮

❛♥❞ wb = 5

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✻✳✸✳ ❘❡s✉❧ts ❛♥❞ ❞✐s❝✉ss✐♦♥ ✶✵✼

✭❛✮ m2 = 1.0

✭❜✮ m2 = 2.0

❋✐❣✉r❡ ✻✳✺✿ ■❇▼ s♥❛♣s❤♦ts ♦❢ t❤❡ st❛t❡ ♦❢ t❤❡ s②st❡♠ ❛t t✐♠❡ t = 400 ❢♦r t❤❡

❝❛s❡ ♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧❡ ❜❛❝t❡r✐❛✳ ❚❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ♦t❤❡r ♣❛r❛♠❡t❡rs ❛r❡

b1 = d1 = 0.1✱ b2 = d2 = 0.1✱ d′1 = d′2 = 0.0 ✭♥♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t✮ ❛♥❞

wb = 5✱ wm = 15✱ wd = 5

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✶✵✽ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

✭❛✮ m2 = 1.0

✭❜✮ m2 = 2.0

❋✐❣✉r❡ ✻✳✻✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s ♦❜t❛✐♥❡❞ ❜② t❤❡ ■❇▼

❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛t t✐♠❡ t = 400 ❢♦r t❤❡ ❝❛s❡ ♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧❡

❜❛❝t❡r✐❛✳ ❚❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ♦t❤❡r ♣❛r❛♠❡t❡rs ❛r❡ b1 = d1 = 0.1✱ b2 = d2 = 0.1✱

d′1 = d′2 = 0.0 ✭♥♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t✮ ❛♥❞ wb = 5✱ wm = 15✱ wd = 5

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✻✳✸✳ ❘❡s✉❧ts ❛♥❞ ❞✐s❝✉ss✐♦♥ ✶✵✾

❋✐❣✉r❡ ✻✳✼✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t✐❡s ♦❢ ♣♦❧②♠❡r ❛s ♣❡r❝❡✐✈❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛

✐♥ t❤❡ ■❇▼ ✭❛✈❡r❛❣❡ ❛♥❞ ♠❛①✮ ❛♥❞ ✐♥ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❚❤❡ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs

❛r❡ b1 = d1 = 0.1✱ b2 = d2 = 0.1✱ d′1 = d′2 = 0.0 ✭♥♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t✮

❛♥❞ wb = 5✱ wm = 15✱ wd = 5

♣♦❧②♠❡r ❝❛❧❝✉❧❛t❡❞ ✐♥ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❋✐❣✉r❡ ✻✳✼ s❤♦✇s t❤❛t ❛s ❧♦♥❣ ❛s t❤❡

♠❛①✐♠✉♠ ✈❛❧✉❡ ♦❢ t❤❡ ❧♦❝❛❧ ♣♦❧②♠❡r ❞❡♥s✐t② ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ ■❇▼

✐s s♠❛❧❧❡r t❤❛♥ t❤❡ ✐♠♠♦❜✐❧✐③❛t✐♦♥ t❤r❡s❤♦❧❞✱ ❜♦t❤ ♠♦❞❡❧s ②✐❡❧❞ s✐♠✐❧❛r r❡s✉❧ts ✇✐t❤

r❡s♣❡❝t t♦ t❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ✭❛♥❞ t❤❡ ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✲ ❞❛t❛

♥♦t s❤♦✇♥✮✳ ❆t t✐♠❡ t ∼ 100 ❛♥❞ ❞✉❡ t♦ st♦❝❤❛st✐❝ ✢✉❝t✉❛t✐♦♥s t❤❡ ♠❛①✐♠✉♠ ✈❛❧✉❡

♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ✐♥ t❤❡ ■❇▼ ✐♥❝r❡❛s❡s ❜❡②♦♥❞ t❤❡ ✐♠♠♦❜✐❧✐③❛t✐♦♥

t❤r❡s❤♦❧❞ ✭❣✐✈❡♥ ❜② m1/m2 = 0.5✮✳ ❚❤✐s ♠❡❛♥s t❤❛t ✐♥ s♦♠❡ r❡❣✐♦♥ ♦❢ t❤❡ ❞♦♠❛✐♥

❛t ❧❡❛st ♦♥❡ ❜❛❝t❡r✐✉♠ ❡①♣❡r✐❡♥❝❡❞ ❛ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ❤✐❣❤❡r t❤❛♥ t❤❡ ✐♠♠♦✲

❜✐❧✐③❛t✐♦♥ t❤r❡s❤♦❧❞ ✈❛❧✉❡✳ ❚❤❡ ❜❛❝t❡r✐✉♠ t❤❛♥ ❜❡❝♦♠❡s ✐♠♠♦t✐❧❡ ❛♥❞ ♠❛② ✐♥✐t✐❛t❡

t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❛ ❝♦❧♦♥②✳ ■t ♠❛② ❤❛♣♣❡♥ t❤❛t t❤❡ st♦❝❤❛st✐❝ ♣♦❧②♠❡r ❞❡t❛❝❤♠❡♥t

r❡♠♦✈❡s ♦♥❡ ♦r ♠♦r❡ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ❢r♦♠ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡ ✐♠♠♦❜✐❧✐③❡❞

❜❛❝t❡r✐✉♠ ✇❤✐❝❤ r❡❞✉❝❡s t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s ❜❡❧♦✇ t❤❡ t❤r❡s❤✲

♦❧❞ ✈❛❧✉❡ ❛♥❞ t❤❡ ✐♠♠♦❜✐❧✐③❡❞ ❜❛❝t❡r✐✉♠ r❡❝♦✈❡r ✐ts ♠♦t✐❧✐t② ✭s❡❡ t❤❡ s♠❛❧❧ ♣❡❛❦ ✐♥

✜❣✉r❡ ✻✳✼ ❛t ✐♥st❛♥t 0✮✳ ❇✉t ✐t ♠❛② ❛❧s♦ ❤❛♣♣❡♥ t❤❛t ❛❞❞✐t✐♦♥❛❧ ♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s

❛r❡ ♣r♦❞✉❝❡❞ ✐♥ t❤❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡ ✐♠♠♦❜✐❧✐③❡❞ ❜❛❝t❡r✐❛ ✇❤✐❝❤ ②✐❡❧❞ t❤❡ ❢♦r✲

♠❛t✐♦♥ ♦❢ ❛ ❝♦❧♦♥②✳ ❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❞♦ ♥♦t ❝❛♣t✉r❡ t❤❡s❡ ♣❤❡♥♦♠❡♥❛ ❜❡❝❛✉s❡

✐t r❡❧✐❡s ♦♥ t❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ✇❤✐❝❤ ✐s st✐❧❧ ❜❡❧♦✇ t❤❡ t❤r❡s❤♦❧❞

✐♠♠♦❜✐❧✐③❛t✐♦♥ ✈❛❧✉❡ ✭s❡❡ ✜❣✉r❡ ✻✳✼✮✳

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✶✶✵ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

❋✐❣✉r❡ ✻✳✽✿ ❊✛❡❝t ♦❢ ♠♦t✐❧✐t② r❛♥❣❡ wm ♦♥ ❝♦❧♦♥② ❢♦r♠❛t✐♦♥✳ ❙❤♦rt✲r❛♥❣❡ ❝♦rr❡✲

s♣♦♥❞s t♦ wm = 5 ❛♥❞ ❧♦♥❣✲r❛♥❣❡ t♦ wm = 15✳ ❖t❤❡r ♣❛r❛♠❡t❡rs ❛r❡ b1 = d1 = 0.1✱

b2 = d2 = 0.1✱ d′1 = d′2 = 0.0 ✭♥♦ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t✮✱ m2 = 2.0✱ wb = 5

❛♥❞ wd = 5

❚❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s ✐♥ t❤❡ ■❇▼ ✐♥❞✉❝❡s s✐❣♥✐✜❝❛♥t ❝❤❛♥❣❡s ♦❢ t❤❡ s♣❛t✐❛❧

♣❛tt❡r♥ ❛♥❞ t❤❡ ❢✉rt❤❡r ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ s②st❡♠✳ ❖t❤❡r ♣r♦❝❡ss❡s ♠❛② r❡✐♥❢♦r❝❡

t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡ ❝♦❧♦♥② ❧✐❦❡ t❤❡ ❞✐✈✐s✐♦♥ ♦❢ t❤❡ ✐♠♠♦❜✐❧✐③❡❞ ❜❛❝t❡r✐✉♠ ♦r t❤❡

❡♥tr❛♣♠❡♥t ♦❢ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✐♥ t❤❡ r❡❣✐♦♥ ✇❤❡r❡ t❤❡ ❧♦❝❛❧ ♣♦❧②♠❡r ❞❡♥s✐t② ✐♥❝r❡❛s❡❞

❜❡②♦♥❞ t❤❡ ✐♠♠♦❜✐❧✐③❛t✐♦♥ t❤r❡s❤♦❧❞ ✈❛❧✉❡✳ ❲❡ ✐♥✈❡st✐❣❛t❡❞ t❤❡ ❡✛❡❝t ♦❢ ✐♥❝r❡❛s✐♥❣

t❤❡ ♠♦t✐❧✐t② r❛♥❣❡ ✭wm✮ ♦♥ t❤❡ ❝♦❧♦♥② ❢♦r♠❛t✐♦♥ ❢♦rm2 = 2.0✳ ❋✐❣✉r❡ ✻✳✽ r❡♣♦rts t❤❡

✐♠♣❛❝t ♦❢ ✐♥❝r❡❛s✐♥❣ t❤❡ ♠♦t✐❧✐t② r❛♥❣❡ ♦♥ t❤❡ ❜❛❝t❡r✐❛ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ❛t

t❤❡ s❤♦rt❡st ❞✐st❛♥❝❡ ξ = dξ ✭✇❤❡r❡ dξ ✐s t❤❡ s♣❛t✐❛❧ r❡s♦❧✉t✐♦♥✮ s✐♠✉❧❛t❡❞ ✉s✐♥❣ t❤❡

■❇▼✳ ❚❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s ✐s tr❛♥s❧❛t❡❞ ❜② t❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ♣❛✐r

❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ❛t ❞✐st❛♥❝❡ dξ✳ ■t ❝❛♥ ❜❡ s❡❡♥ ❢r♦♠ ✜❣✉r❡ ✻✳✽ t❤❛t ✐♥ t❤❡ ❝❛s❡

♦❢ ❧♦♥❣✲r❛♥❣❡ ♠♦t✐❧✐t②✱ t❤❡ ♣❡❛❦ ✐♥ t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ♦❝❝✉rs ❛t t = 200

✇❤✐❧❡ t❤❡ s❛♠❡ ♣❡❛❦ ♦❝❝✉rs ❛t t✐♠❡ t = 350 ✐♥ t❤❡ ❝❛s❡ ♦❢ s❤♦rt✲r❛♥❣❡ ♠♦t✐❧✐t②✳ ❚❤❡

❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s s❡❡♠s t♦ ❜❡ ❢❛st❡r ✐♥ t❤❡ ❝❛s❡ ♦❢ ❧♦♥❣✲r❛♥❣❡ ♠♦t✐❧✐t②✳ ❲❤✐❧❡

✐♥❝r❡❛s✐♥❣ t❤❡ ♠♦t✐❧✐t② r❛♥❣❡ ♦❢ t❤❡ ❜❛❝t❡r✐❛ ♣r❡✈❡♥t❡❞ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s ✐♥

t❤❡ ❝❛s❡ ♦❢ t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦❞❡❧✱ ✐t ✐s ❧✐❦❡❧② t♦ ❤❛✈❡ t❤❡ ✐♥✈❡rs❡ ❡✛❡❝t ✐♥

t❤❡ ❝❛s❡ ♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t②✳ ❚❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ ♠♦t✐❧✐t② r❛♥❣❡ ❛❝❝❡❧❡r❛t❡

t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s✳ ❆ ♣♦ss✐❜❧❡ ❡①♣❧❛♥❛t✐♦♥ ✐s t❤❛t ♠♦t✐❧❡ ❜❛❝t❡r✐❛ tr❛✈❡❧✐♥❣

♦✈❡r ❧♦♥❣ ❞✐st❛♥❝❡ ❤❛✈❡ ♠♦r❡ ❝❤❛♥❝❡ t♦ ❜❡ tr❛♣♣❡❞ ✐♥ ❛ ❧♦❝❛t✐♦♥ ✇✐t❤ ❤✐❣❤ ❞❡♥s✐t②

♦❢ ♣♦❧②♠❡r t❤❛♥ ❜❛❝t❡r✐❛ tr❛✈❡❧✐♥❣ ♦✈❡r s❤♦rt ❞✐st❛♥❝❡s✳

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✻✳✹✳ ❈♦♥❝❧✉s✐♦♥ ✶✶✶

❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t

❙♦ ❢❛r✱ ✇❡ ❝♦♥s✐❞❡r❡❞ t❤❛t ❞❡t❛❝❤♠❡♥t ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❛♥❞ ♣♦❧②♠❡r ♦❝❝✉rs ❛t ❛

✜①❡❞ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t r❛t❡ ✭d1 = d2 = 0.1 ❛♥❞ d′1 = d′2 = 0✮✳ ◆♦✇ ✇❡ ✐♥✈❡st✐❣❛t❡

t❤❡ ❝❛s❡ ✇❤❡r❡ t❤❡ ❞❡t❛❝❤♠❡♥t r❛t❡s ♦❢ ♣♦❧②♠❡r ❛♥❞ ❜❛❝t❡r✐❛ ✐♥❝r❡❛s❡ ✇✐t❤ t❤❡ ❧♦❝❛❧

❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r✳ ❚❤✐s ♠❡❛♥s t❤❛t ❜❛❝t❡r✐❛ ❛♥❞ ♣♦❧②♠❡r ❡♥❝❧♦s❡❞ ✇✐t❤✐♥ ❝♦❧♦♥✐❡s

✇✐❧❧ ❡①♣❡r✐❡♥❝❡ ❤✐❣❤❡r ❞❡t❛❝❤♠❡♥t r❛t❡s t❤❛t t❤❡✐r ❞✐s♣❡rs❡❞ ❝♦✉♥t❡r♣❛rts✳ ❋✐❣✉r❡

✻✳✾ s❤♦✇s ■❇▼ s♥❛♣s❤♦ts ♦❢ t❤❡ ♣❛tt❡r♥ ❢♦r t✇♦ ❞✐✛❡r❡♥t ✈❛❧✉❡s ♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

❞❡t❛❝❤♠❡♥t r❛t❡s d′1 = d′2 = 0.05 ❛♥❞ d′1 = d′2 = 0.1✳ ■♥❝r❡❛s✐♥❣ t❤❡ ❡✛❡❝t ♦❢ t❤❡

❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t ♣r❡✈❡♥ts t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡ ❝♦❧♦♥✐❡s✳ ❚❤✐s ✐s ❝♦♥✲

✜r♠❡❞ ❜② t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s ✐♥ ✜❣✉r❡ ✻✳✶✵ ✇❤❡r❡ t❤❡ ♣❡❛❦ r❡❛❝❤❡❞ ❜② t❤❡

♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ✐s ❧♦✇❡r ✐♥ t❤❡ ❝❛s❡ ♦❢ ❤✐❣❤❡r ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t

r❛t❡s✱ ✐♥❞✐❝❛t✐♥❣ ❛ ❧♦✇❡r ❧❡✈❡❧ ♦❢ ❛❣❣r❡❣❛t✐♦♥ ♦❢ t❤❡ ❜❛❝t❡r✐❛✳ ❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧

❢❛✐❧s ✐♥ ❝❛♣t✉r✐♥❣ t❤❡ ❝♦❧♦♥✐❡s ❢♦r♠❛t✐♦♥ ❛♥❞ t❤❡ ❡✛❡❝t ♦❢ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

❞❡t❛❝❤♠❡♥t ✐s ✉♥❞❡r✲❡st✐♠❛t❡❞ ✐♥ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳

❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t ❤❛s ❛♥ ✐♠♣❛❝t ♦♥ t❤❡ ❛✈❡r❛❣❡✲❞❡♥s✐t② ♦❢ t❤❡ ❜❛❝✲

t❡r✐❛ ❛♥❞ ♣♦❧②♠❡r✳ ❋✐❣✉r❡ ✻✳✶✶ s❤♦✇s t❤❡ t✐♠❡ ❝♦✉rs❡ ♦❢ t❤❡ ❞❡♥s✐t② ♦❢ ❜❛❝t❡r✐❛

❛♥❞ ♣♦❧②♠❡r ❝❛❧❝✉❧❛t❡❞ ✇✐t❤ t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❋♦r ❤✐❣❤ ❞❡♥s✐t②✲

❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡s✱ t❤❡ ❡q✉✐❧✐❜r✐✉♠ ❞❡♥s✐t✐❡s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❛r❡ ❧♦✇❡r

t❤❛♥ t❤❡ ❞❡♥s✐t✐❡s t❤❛t r❡s✉❧ts ❢r♦♠ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❚❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s

✐♥❝r❡❛s❡s t❤❡ ❞❡t❛❝❤♠❡♥t r❛t❡ ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ❜❛❝t❡r✐❛ ✇❤✐❝❤ ②✐❡❧❞s ❧♦✇❡r ❡q✉✐✲

❧✐❜r✐✉♠ ❞❡♥s✐t✐❡s✳ ❚❤❡ ❞✐✛❡r❡♥❝❡ ❜❡t✇❡❡♥ ❜♦t❤ ♠♦❞❡❧s ✈❛♥✐s❤❡s ❢♦r ❤✐❣❤❡r ❞❡♥s✐t②✲

❞❡t❛❝❤♠❡♥t r❛t❡s ❜❡❝❛✉s❡ ♦❢ t❤❡ ❛❜s❡♥❝❡ ♦❢ ❝♦❧♦♥✐❡s ❢♦r♠❛t✐♦♥✳

✻✳✹ ❈♦♥❝❧✉s✐♦♥

❲❡ ❞❡r✐✈❡❞ ❛ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ❡q✉❛t✐♦♥s ♦❢ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ t❤❛t ❞❡s❝r✐❜❡s

❝♦❧♦♥✐❡s ❢♦r♠❛t✐♦♥ ❞✉❡ t♦ t♦ ❜❛❝t❡r✐❛ ♠♦t✐❧✐t② r❡❞✉❝t✐♦♥ ❜② ❛ s❡❧❢✲♣r♦❞✉❝❡❞ ♣♦❧②♠❡r✳

❇♦t❤ ♠♦❞❡❧s ❛❝❝♦✉♥t ❢♦r ✜✈❡ ♣r♦❝❡ss❡s t❛❦✐♥❣ ♣❧❛❝❡ ❛t t❤❡ ❧❡✈❡❧ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❚♦

❛♥❛❧②③❡ t❤❡s❡ ♠♦❞❡❧s ✇❡ ♣r♦❝❡❡❞ ♣r♦❣r❡ss✐✈❡❧② st❛rt✐♥❣ ✇✐t❤ ❛ ❞❡♥s✐t② ✐♥❞❡♣❡♥❞❡♥t

♠♦❞❡❧ ♦❜t❛✐♥❡❞ ❜② s❡tt✐♥❣ t❤❡ ♠♦t✐❧✐t② ❛♥❞ ❞❡t❛❝❤♠❡♥t ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ❢❛❝t♦rs

t♦ ③❡r♦✳ ❲❡ s❤♦✇ t❤❛t ✐♥ t❤❡ ❛❜s❡♥❝❡ ♦❢ ♠♦t✐❧✐t②✱ ❝♦❧♦♥✐❡s ❢♦r♠ ❛s ❛ r❡s✉❧t ♦❢ t❤❡

❧♦✇ ❞✐s♣❡rs✐♦♥ ♦❢ t❤❡ ❞❛✉❣❤t❡r ❝❡❧❧s ❛♥❞ t❤❛t ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② t❡♥❞ t♦

✐♥❝r❡❛s❡ t❤✐s ❞✐s♣❡rs✐♦♥ r❛♥❣❡ ♣r❡✈❡♥t✐♥❣ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s✳ ▼♦♠❡♥t ♠♦❞❡❧

❛♥❞ t❤❡ ■❇▼ ❝♦♠♣❛r❡ ✈❡r② ✇❡❧❧ ✐♥ t❤❡ ❝❛s❡ ♦❢ ❞❡♥s✐t② ✐♥❞❡♣❡♥❞❡♥t ♠♦❞❡❧✳ ❚❤❡

♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥ ♦❢ t❤❡ ❜❛❝t❡r✐❛ ♣♦s✐t✐♦♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ s✐♠✉❧❛t✐♦♥

❝❛♣t✉r❡❞ t❤❡ ♠❛✐♥ ❢❡❛t✉r❡s ♦❢ t❤❡ s✐♠✉❧❛t❡❞ ♣❛tt❡r♥s ❛♥❞ ❛r❡ ✐♥ ❛ ❣♦♦❞ ❛❣r❡❡♠❡♥t

✇✐t❤ t❤♦s❡ ②✐❡❧❞❡❞ ❜② t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳

❙t❛rt✐♥❣ ❢r♦♠ t❤❡ ❝❛s❡ ♦❢ ❜❛❝t❡r✐❛ ✇✐t❤ ❛ ❧♦♥❣✲♠♦t✐❧✐t② r❛♥❣❡ ✭♥♦ ❝♦❧♦♥✐❡s ❢♦r✲

♠❛t✐♦♥✮ ✇❡ t❤❡♥ ✐♥tr♦❞✉❝❡❞ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t②✳ ❖✉r r❡s✉❧ts s❤♦✇❡❞ t❤❛t

❝♦❧♦♥✐❡s ❢♦r♠ ❞✉❡ t♦ t❤❡ ✐♠♠♦❜✐❧✐③❛t✐♦♥ ♦❢ ❜❛❝t❡r✐❛ ✐♥ t❤❡ ❧♦❝❛t✐♦♥ ✇❤❡r❡ t❤❡ ❧♦❝❛❧

❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ✐♥❝r❡❛s❡s ❛❜♦✈❡ ❛ t❤r❡s❤♦❧❞ ✈❛❧✉❡✳ ❲❤✐❧❡ ✐♥ ❛✈❡r❛❣❡✱ t❤❡ ❧♦❝❛❧

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✶✶✷ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

✭❛✮ d1 = d′2 = 0.05

✭❜✮ d′1 = d′2 = 0.1

❋✐❣✉r❡ ✻✳✾✿ ■❇▼ s♥❛♣s❤♦ts ♦❢ t❤❡ st❛t❡ ♦❢ t❤❡ s②st❡♠ ❛t t✐♠❡ t = 400 ❢♦r t❤❡ ❝❛s❡

♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t✳ b1 = b2 = 0.12✱ d1 = d2 = 0.1✱ m1 = 1.0✱

m2 = 2.0✱wb = 5✱ wm = 15 ❛♥❞ wd = 5

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✻✳✹✳ ❈♦♥❝❧✉s✐♦♥ ✶✶✸

✭❛✮ d1 = d′2 = 0.05

✭❜✮ d1 = d′2 = 0.1

❋✐❣✉r❡ ✻✳✶✵✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ r❛❞✐❛❧ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥s ♦❜t❛✐♥❡❞ ❜② t❤❡ ■❇▼

❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛t t✐♠❡ t = 400✳ ❚❤❡ ♠♦❞❡❧s ♣❛r❛♠❡t❡rs ❛r❡✿b1 = b2 = 0.12✱

d1 = d2 = 0.1✱ m1 = 1.0✱ m2 = 2.0✱wb = 5✱ wm = 15 ❛♥❞ wd = 5

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✶✶✹ ❈❤❛♣t❡r ✻✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ■❇▼

✭❛✮ d1 = d′2 = 0.05

✭❜✮ d1 = d′2 = 0.1

❋✐❣✉r❡ ✻✳✶✶✿ ❈♦♠♣❛r✐s♦♥ ♦❢ t❤❡ t✐♠❡ ❝♦✉rs❡ ♦❢ t❤❡ ❞❡♥s✐t✐❡s ♦❢ ❜❛❝t❡r✐❛ Nb ❛♥❞

♣♦❧②♠❡r Np ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❛♥❞ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧✳ ❚❤❡ ♠♦❞❡❧s ♣❛r❛♠❡t❡rs

❛r❡✿b1 = b2 = 0.12✱ d1 = d2 = 0.1✱ m1 = 1.0✱ m2 = 2.0✱wb = 5✱ wm = 15 ❛♥❞ wd = 5

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✻✳✹✳ ❈♦♥❝❧✉s✐♦♥ ✶✶✺

❞❡♥s✐t② ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧s r❡♠❛✐♥ ❜❡❧♦✇ t❤❡ ✐♠♠♦❜✐❧✐③❛t✐♦♥ t❤r❡s❤♦❧❞✱

✢✉❝t✉❛t✐♦♥s ✐♥ ❧♦❝❛❧ ♣♦❧②♠❡r ❞❡♥s✐t✐❡s ✇♦✉❧❞ ❤❛✈❡ ♣✉s❤❡❞ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥✲

s✐t② ❛❜♦✈❡ t❤❡ ✐♠♠♦❜✐❧✐③❛t✐♦♥ t❤r❡s❤♦❧❞ ✇❤✐❝❤ ✐♥✐t✐❛t❡❞ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s✳

❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❞♦ ♥♦t ❝❛♣t✉r❡ t❤✐s ♣r♦❝❡ss✱ ❛s t❤❡ ❞②♥❛♠✐❝s ♦❢ t❤❡ ♠♦♠❡♥ts ✐s

❜❛s❡❞ ♦♥ t❤❡ ❛✈❡r❛❣❡ ❧♦❝❛❧ ❞❡♥s✐t②✳

❋✉rt❤❡r♠♦r❡✱ ✇❡ ✐♥✈❡st✐❣❛t❡❞ ❤♦✇ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s ✐♥ t❤❡ ❝❛s❡ ♦❢ ❞❡♥✲

s✐t② ❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② ✐s ❛✛❡❝t❡❞ ❜② t❤❡ s✐③❡ ♦❢ t❤❡ ♠♦t✐❧✐t② ❦❡r♥❡❧ sm✳ ❙✉r♣r✐s✲

✐♥❣❧② ✐♥❝r❡❛s✐♥❣ t❤❡ ♠♦t✐❧✐t② r❛♥❣❡ ♦❢ t❤❡ ❜❛❝t❡r✐❛ t❡♥❞ t♦ ♣r♦♠♦t❡ t❤❡ ❢♦r♠❛t✐♦♥

♦❢ ❝♦❧♦♥✐❡s✳ ▲♦♥❣ r❛♥❣❡ ♠♦t✐❧✐t②✱ ❛❧❧♦✇✐♥❣ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ t♦ tr❛✈❡❧ ♦✈❡r ❧♦♥❣❡r ❞✐s✲

t❛♥❝❡s✱ ✐♥❝r❡❛s❡s t❤❡✐r ❝❤❛♥❝❡ t♦ ❝r♦ss ❧♦❝❛t✐♦♥s ✇❤❡r❡ t❤❡ ♣♦❧②♠❡r ❞❡♥s✐t② ❡①❝❡❡❞s

t❤❡ ✐♠♠♦❜✐❧✐③❛t✐♦♥ t❤r❡s❤♦❧❞ ✈❛❧✉❡✳

❋✐♥❛❧❧②✱ t❤❡ ✐♥✢✉❡♥❝❡ ♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t ♦❢ ♣♦❧②♠❡r ❛♥❞ ❜❛❝t❡r✐❛

❣♦❡s t❤❡ ♦t❤❡r ❞✐r❡❝t✐♦♥ ♦❢ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t②✳ ❉❡t❛❝❤♠❡♥t ✐s ❛ss✉♠❡❞ t♦

✐♥❝r❡❛s❡ ✇✐t❤ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r ❡①♣❡r✐❡♥❝❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤✉s

❞❡♣❡♥❞✐♥❣ ♦♥ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t ♣❛r❛♠❡t❡rs ❝♦❧♦♥✐❡s

♠❛② ♦r ♠❛② ♥♦t ❢♦r♠✳

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❈❤❛♣t❡r ✼

❊①♣❧♦r✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡

♣❛tt❡r♥s ✐♥ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢ ❛

♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤

♠♦t✐❧❡ ❜❛❝t❡r✐❛

❈♦♥t❡♥ts

✼✳✶ ❙✐♠♣❧✐✜❡❞ ■❇▼ ❢♦r ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

♠♦t✐❧❡ ❜❛❝t❡r✐❛ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✼

✼✳✷ ◆✉♠❡r✐❝❛❧ ❡①♣❧♦r❛t✐♦♥ ♦❢ t❤❡ ■❇▼ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✶✾

✼✳✸ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✷✵

✼✳✹ ❉✐s❝✉ss✐♦♥ ❛♥❞ ❝♦♥❝❧✉s✐♦♥ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✷✾

❲❡ ♣r♦♣♦s❡ t♦ ❢✉rt❤❡r s✐♠♣❧✐❢② t❤❡ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ✭■❇▼✮ ♣r❡s❡♥t❡❞ ✐♥ t❤❡

♣r❡✈✐♦✉s ❝❤❛♣t❡r ❛♥❞ ❞✐s❝✉ss ✐ts ❛♣♣r♦①✐♠❛t✐♦♥ ✉s✐♥❣ ♠♦♠❡♥t ♠♦❞❡❧s✳ ❚❤❡ ♠❛✐♥

s✐♠♣❧✐✜❝❛t✐♦♥ ✐s t❤❛t ✐♥❞✐✈✐❞✉❛❧s ♠♦t✐❧✐t② ❛♥❞ ❞❡t❛❝❤♠❡♥t ❞❡♣❡♥❞ ♥♦✇ ❞✐r❡❝t❧② ♦♥

t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s r❛t❤❡r t❤❛♥ ♦♥ t❤❡ ❡①❝r❡t❡❞ ♣♦❧②♠❡r✳ ❍❡♥❝❡ ✇❡

❞♦ ♥♦t ❝♦♥s✐❞❡r ♣♦❧②♠❡r ❞②♥❛♠✐❝ ✐♥ t❤✐s ❝❤❛♣t❡r✳

❚❤❡ ❝❤❛♣t❡r ✐s ♦r❣❛♥✐③❡❞ ✐♥ ❢♦✉r s❡❝t✐♦♥s✿ ✐♥ t❤❡ ✜rst s❡❝t✐♦♥ ✇❡ ❞❡s❝r✐❜❡ t❤❡

s✐♠♣❧✐✜❡❞ ■❇▼✳ ■♥ t❤❡ s❡❝♦♥❞ s❡❝t✐♦♥ ✇❡ ❡①♣❧♦r❡ t❤❡ ♣❛tt❡r♥ ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼

❛♥❞ ❝♦♠♣❛r❡ t❤❡s❡ ♣❛tt❡r♥s q✉❛❧✐t❛t✐✈❡❧② t♦ ❡①♣❡r✐♠❡♥t❛❧ ❜✐♦✜❧♠ ♣❛tt❡r♥s ❛♥❞ t♦

t❤❡ ♣❛tt❡r♥ ♦❜t❛✐♥❡❞ ✇✐t❤ t❤❡ ■❇▼ ✐♥❝❧✉❞✐♥❣ t❤❡ ♣♦❧②♠❡r ✭❝❤❛♣t❡r ✻✮✳ ❋✐♥❛❧❧② ✇❡

❞✐s❝✉ss t❤❡ ❛♣♣r♦①✐♠❛t✐♦♥ ♦❢ t❤❡ ■❇▼ ✉s✐♥❣ ♠♦♠❡♥t ❛♣♣r♦❛❝❤ ❛ss❡ss t❤❡ t❡❝❤♥✐❝❛❧

❞✐✣❝✉❧t✐❡s ✐♥ s♦❧✈✐♥❣ ♠♦♠❡♥t ❡q✉❛t✐♦♥s ✇✐t❤ ♠♦t✐❧✐t②✳

✼✳✶ ❙✐♠♣❧✐✜❡❞ ■❇▼ ❢♦r ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ❞❡♥s✐t②✲

❞❡♣❡♥❞❡♥t ♠♦t✐❧❡ ❜❛❝t❡r✐❛

❚❤❡ ■❇▼ t❤❛t ✇❡ ❞❡s❝r✐❜❡ ✐♥ t❤✐s s❡❝t✐♦♥ ✐s ❛♥ ❡①t❡♥s✐♦♥ ♦❢ t❤❡ ■❇▼ ♣r❡s❡♥t❡❞ ✐♥

❝❤❛♣t❡r ✹ t❤❛t ✐♥❝❧✉❞❡s ❞✐✈✐s✐♦♥ ❛♥❞ ❞❡♥s✐t② ❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t✳ ■♥ ❛❞❞✐t✐♦♥ t♦

t❤❡s❡ ♣r♦❝❡ss❡s ✱ ✇❡ ✐♥❝❧✉❞❡ ❛ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② ♣r♦❝❡ss✳ ❚❤❡ r❡s✉❧t❛♥t

■❇▼ ❝♦♥s✐❞❡rs t❤❡ ❢♦❧❧♦✇✐♥❣ t❤r❡❡ ♣r♦❝❡ss❡s✿

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✶✶✽

❈❤❛♣t❡r ✼✳ ❊①♣❧♦r✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s ✐♥ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢

❛ ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡ ❜❛❝t❡r✐❛

• ❉✐✈✐s✐♦♥ ♣r♦❝❡ss✿ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ✐♥ ❧♦❝❛t✐♦♥ x = (x1, x2) ❤❛s ❛ ♣r♦❜❛❜✐❧✐t② ✭♣❡r

✉♥✐t ♦❢ t✐♠❡✮ B(x, x′) t♦ ♣r♦❞✉❝❡ ❛ ♥❡✇❜♦r♥ ❧♦❝❛t❡❞ ✐♥ x′ ❣✐✈❡♥ ❜②✿

B(x, x′) = b1 ✭✼✳✶✮

✇❤❡r❡ b1 ✐s ❛ ❝♦♥st❛♥t ❞✐✈✐s✐♦♥ r❛t❡✳

• ❉❡t❛❝❤♠❡♥t ♣r♦❝❡ss✿ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ✐♥ ❧♦❝❛t✐♦♥ x ❞❡t❛❝❤❡s ✇✐t❤ ❛ ❞❡♥s✐t②✲

❞❡♣❡♥❞❡♥t ♣r♦❜❛❜✐❧✐t② D(x) ❣✐✈❡♥ ❜②✿

D(x) = d1 + d′1plocd (x) ✭✼✳✷✮

✇❤❡r❡ d1 ❛♥❞ d′1 ❛r❡ t❤❡ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❛♥❞ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡✲

t❛❝❤♠❡♥t r❛t❡s ❛♥❞ plocd (x) ✐s t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♣❡r❝❡✐✈❡❞ ❜② t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ x✳

plocd (x) ♠❡❛s✉r❡s t❤❡ ✐♠♣❛❝t ♦❢ t❤❡ ♥❡✐❣❤❜♦r✐♥❣ ✐♥❞✐✈✐❞✉❛❧s ♦♥ t❤❡ ❞❡t❛❝❤♠❡♥t

♣r♦❜❛❜✐❧✐t② ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ x✳ ❲❡ ❝❛❧❝✉❧❛t❡❞ t❤✐s ❧♦❝❛❧ ❞❡♥s✐t② ✉s✐♥❣ t❤❡

❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ K(||x− x′||/wd) ❣✐✈❡♥ ❜②✿

K(||x− x′||

wd=

{

1/wd ✐❢ ||x− x′|| < wd

0 ❡❧s❡✭✼✳✸✮

• ▼♦t✐❧✐t②✿ ✇❡ ♠♦❞❡❧ ✐♥❞✐✈✐❞✉❛❧s ♠♦t✐❧✐t② ❛s ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣r♦❝❡ss s✉❝❤

t❤❛t t❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡ ❢♦r ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❧♦❝❛t❡❞ ✐♥ x t♦ ♠♦✈❡ t♦

❛ ❧♦❝❛t✐♦♥ x′ ❞❡❝r❡❛s❡s ✇✐t❤ t❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐♥

x✳ ❚❤✉s✱ ✐♥ t❤✐s ♠♦❞❡❧ t❤❡ ♥❡✐❣❤❜♦r ♦❢ ❛ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧ t❡♥❞ t♦ r❡❞✉❝❡s ✐ts

♠♦t✐❧✐t② ❛♥❞ ✐♥❝r❡❛s❡ ✐ts ❞❡t❛❝❤♠❡♥t r❛t❡✳ ❚❤❡ ♣r♦❜❛❜✐❧✐t② ♣❡r ✉♥✐t ♦❢ t✐♠❡ ♦❢

❛♥ ✐♥❞✐✈✐❞✉❛❧ t♦ ♠♦✈❡ ❢r♦♠ x t♦ x′ ✐s ❣✐✈❡♥ ❜②✿

M(x, x′) = [m1 −m2ploc(x,wv)]K((x− x′)/wm) ✭✼✳✹✮

✇❤❡r❡ m1 ❛♥❞ m2 ❛r❡ r❡s♣❡❝t✐✈❡❧② t❤❡ ❞❡♥s✐t② ✐♥❞❡♣❡♥❞❡♥t ❛♥❞ t❤❡ ❞❡♥s✐t②

❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② ♣❛r❛♠❡t❡rs✱ ploc(x,wv) ✐s t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ❜❛❝t❡r✐❛ ♣❡r✲

❝❡✐✈❡❞ ❜② ❛♥ ✐♥❞✐✈✐❞✉❛❧ ✐♥ x ❛♥❞ ❝❛❧❝✉❧❛t❡❞ ✉s✐♥❣ ❛ ✉♥✐❢♦r♠ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧

✇✐t❤ ❛ s✐③❡ wv ❛♥❞ m(x−x′)✳ ❚❤❡ ❡①♣r❡ss✐♦♥ [m1−m2ploc(x,wv)] ❝♦rr❡s♣♦♥❞s

t♦ t❤❡ ♠♦t✐♦♥ ♣r♦❜❛❜✐❧✐t② ✭♣❡r ✉♥✐t ♦❢ t✐♠❡✮ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ x✳ ❚❤✐s ❡①✲

♣r❡ss✐♦♥ s❤♦✉❧❞ ❜❡ ♣♦s✐t✐✈❡✳ ■❢ t❤❡ ❧♦❝❛❧ ♣❡r❝❡✐✈❡❞ ❞❡♥s✐t② ploc(x,wv) ✐s ❤✐❣❤❡r

t❤❛t t❤❡ ✈❛❧✉❡ ♦❢ m1/m2 t❤❛♥ t❤❡ ♠♦t✐♦♥ ♣r♦❜❛❜✐❧✐t② ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ ✐♥ x ✐s

s❡t t♦ ③❡r♦✳

❆ s✐♠✉❧❛t✐♦♥ ✐s ✐♥✐t✐❛❧✐③❡❞ ✇✐t❤ ❛ ♥✉♠❜❡r N0 ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ✉♥✐❢♦r♠❧② ❞✐str✐❜✉t❡❞

♦✈❡r t❤❡ ❞♦♠❛✐♥✳ ❚❤❡ ♠♦❞❡❧ ♣❛r❛♠❡t❡rs ❛r❡ s✉♠♠❛r✐③❡❞ ✐♥ t❛❜❧❡ ✼✳✶✳

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✼✳✷✳ ◆✉♠❡r✐❝❛❧ ❡①♣❧♦r❛t✐♦♥ ♦❢ t❤❡ ■❇▼ ✶✶✾

P❛r❛♠❡t❡rs ❉❡s❝r✐♣t✐♦♥ ❱❛❧✉❡

L ❉♦♠❛✐♥ s✐③❡ 201× 201

∆L ❙♣❛t✐❛❧ ❞✐s❝r❡t✐③❛t✐♦♥ 1

b1 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ❜❛❝t❡r✐❛ ❞✐✈✐s✐♦♥ r❛t❡ 0.1

d1 ❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡ 0.0

d2 ❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❞❡t❛❝❤♠❡♥t r❛t❡ 0.4

m1 ❉❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡ 0.0 ♦r 1.0

m2 ❉❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❛t❡ 0.0 ♦r 3.0

wb ❯♥✐❢♦r♠ ❞✐✈✐s✐♦♥ ❛♥❞ ♣♦❧②♠❡r ♣r♦❞✉❝t✐♦♥ ❦❡r♥❡❧ s✐❞❡ ✈❛r✐❛❜❧❡

wd ❯♥✐❢♦r♠ ❞❡t❛❝❤♠❡♥t ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ s✐❞❡ ✈❛r✐❛❜❧❡

wv ❯♥✐❢♦r♠ ♠♦t✐❧✐t② ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ s✐❞❡ ✈❛r✐❛❜❧❡

wm ❯♥✐❢♦r♠ ♠♦t✐❧✐t② ❦❡r♥❡❧ ✈❛r✐❛❜❧❡

❚❛❜❧❡ ✼✳✶✿ ▼♦❞❡❧ ♣❛r❛♠❡t❡rs

❆ ♠❛❥♦r ❞✐✛❡r❡♥❝❡ ♦❢ t❤✐s s✐♠♣❧✐✜❡❞ ■❇▼ ✇✐t❤ t❤❡ ■❇▼ ♣r❡s❡♥t❡❞ ✐♥ t❤❡ ♣r❡✈✐♦✉s

❝❤❛♣t❡r ✭❈❤❛♣t❡r ✻✮ ✐s t❤❛t t❤❡ ❞❡t❛❝❤♠❡♥t ❛♥❞ t❤❡ ♠♦t✐❧✐t② ♣r♦❜❛❜✐❧✐t✐❡s ❞❡♣❡♥❞ ♦♥

t❤❡ ❞❡♥s✐t② ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s t❤❡♠s❡❧✈❡s r❛t❤❡r t❤❛♥ ♦♥ t❤❡ ❞❡♥s✐t② ♦❢ t❤❡ ❡①❝r❡t❡❞

♣r♦❞✉❝t✳ ❚❤❡ ✐♠♣❧✐❝✐t ❛ss✉♠♣t✐♦♥ ❜❡❤✐♥❞ t❤✐s s✐♠♣❧✐✜❝❛t✐♦♥ ✐s t❤❛t t❤❡ ❡①❝r❡t❡❞

♣r♦❞✉❝ts ❛♥❞ t❤❡ ✐♥❞✐✈✐❞✉❛❧s s♣❛t✐❛❧ ❞✐str✐❜✉t✐♦♥s ❛r❡ ❝♦rr❡❧❛t❡❞ s✉❝❤ t❤❛t t❤❡ ❧♦❝❛❧

❛❝❝✉♠✉❧❛t✐♦♥ ♦❢ t❤❡ ✜rst ✐♥❞✉❝❡s ✭❛♥❞✴♦r r❡s✉❧ts ❢r♦♠✮ t❤❡ ❛❝❝✉♠✉❧❛t✐♦♥ ♦❢ t❤❡

s❡❝♦♥❞✳

✼✳✷ ◆✉♠❡r✐❝❛❧ ❡①♣❧♦r❛t✐♦♥ ♦❢ t❤❡ ■❇▼

❚❤♦✉❣❤ s✐♠♣❧❡✱ t❤❡ ■❇▼ ❞❡s❝r✐❜❡❞ ❛❜♦✈❡ ②✐❡❧❞s ❛ ❞✐✈❡rs✐t② ♦❢ ♣❛tt❡r♥s r❛♥❣✐♥❣

❢r♦♠ ✉♥✐❢♦r♠ ❞✐str✐❜✉t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s t♦ ✐s♦❧❛t❡❞ ❝♦❧♦♥② ❛♥❞ ❧❛❜②r✐♥t❤✲❧✐❦❡

♣❛tt❡r♥s✳ ■♥ ❛ r❡❝❡♥t ♣❛♣❡r ❳❛✈✐❡r ❡t ❛❧✳ ❬❳❛✈✐❡r ✷✵✵✾❪ s❤♦✇❡❞ t❤❛t s✐♠✐❧❛r ♣❛tt❡r♥s

❛r✐s❡ ✐♥ ❧❛❜♦r❛t♦r② ❝✉❧t✉r❡ ♦❢ t❤❡ ❜✐♦✜❧♠ ❢♦r♠✐♥❣ str❛✐♥ P✳ ❛❡r✉❣✐♥♦s❛ ✭✜❣✉r❡ ✼✳✶✮✳

❚❤❡② ❡①♣❧❛✐♥❡❞ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡s❡ ♣❛tt❡r♥s ❜② s❝❛❧❡✲❞❡♣❡♥❞❡♥t ✐♥t❡r❛❝t✐♦♥s ❜❡✲

t✇❡❡♥ ♥✉tr✐❡♥t ❝♦♠♣❡t✐t✐♦♥ ❛♥❞ ♠❡❝❤❛♥✐❝❛❧ ♣✉s❤✐♥❣✳ ❆t ❧♦✇ ♥✉tr✐❡♥t ❞❡♥s✐t✐❡s t❤❡

❜❛❝t❡r✐❛ ❢♦r♠❡❞ ✐s♦❧❛t❡❞ ❝♦❧♦♥✐❡s✳ ❚❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡ ♥✉tr✐❡♥t ❝♦♥❝❡♥tr❛t✐♦♥ ✐♥❞✉❝❡❞

❛ tr❛♥s✐t✐♦♥ t♦ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s t❤❡♥ t♦ t❤❡ ❞❡♥s❡ ❜✐♦✜❧♠ ♣❛tt❡r♥✳

❖✉r s✐♠♣❧✐✜❡❞ ♠♦❞❡❧ ❝❛♥ r❡♣r♦❞✉❝❡ s✐♠✐❧❛r tr❛♥s✐t✐♦♥s ❢r♦♠ t❤❡ ✐s♦❧❛t❡❞ ❝♦❧♦♥②

♣❛tt❡r♥ t♦ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥✱ ❛s ✐❧❧✉str❛t❡❞ ✐♥ ✜❣✉r❡s ✼✳✷ ❛♥❞ ✼✳✸✱ ❡✐t❤❡r

❜② ✐♥❝r❡❛s✐♥❣ ♣r♦❣r❡ss✐✈❡❧② t❤❡ ❞✐✈✐s✐♦♥ r❛t❡ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✭✜❣✉r❡ ✼✳✸✮ ♦r ❜②

✐♥❝r❡❛s✐♥❣ t❤❡ ✈❛❧✉❡ ♦❢ t❤❡ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♣❛r❛♠❡t❡r m2✳ ❲❡ ✐❞❡♥t✐❢② ❜❛❝t❡r✐❛

♠♦t✐❧✐t② ❛♥❞ ❞❡t❛❝❤♠❡♥t ❛s t✇♦ ♣♦t❡♥t✐❛❧ ♣r♦❝❡ss❡s t❤❛t ♠❛② ②✐❡❧❞ ❧❛❜②r✐♥t❤✲❧✐❦❡

♣❛tt❡r♥s✳

❋✐❣✉r❡ ✼✳✹ s❤♦✇s t❤❡ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ s✐♠♣❧✐✜❡❞ ♠♦❞❡❧ ❛r❡ ❝♦♠♣❛r❛❜❧❡ t♦

t❤♦s❡ t❤❛t ♠❛② ❜❡ ♦❜t❛✐♥❡❞ ✇✐t❤ t❤❡ ■❇▼ ✐♥❝❧✉❞✐♥❣ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ♣♦❧②♠❡r

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✶✷✵

❈❤❛♣t❡r ✼✳ ❊①♣❧♦r✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s ✐♥ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢

❛ ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡ ❜❛❝t❡r✐❛

❋✐❣✉r❡ ✼✳✶✿ ❬❳❛✈✐❡r ✷✵✵✾❪

✭❈❤❛♣t❡r ✻✮✳ ❚❤❡s❡ r❡s✉❧ts t❤❛t t❤❡ ❡①♣❧✐❝✐t ❝♦♥s✐❞❡r❛t✐♦♥ ♦❢ t❤❡ ♣♦❧②♠❡r ♠❛② ♥♦t

❜❡ ♥❡❝❡ss❛r② ❢♦r t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ t❤❡s❡ s♣❛t✐❛❧ ♣❛tt❡r♥s✳

■♥ ♦r❞❡r t♦ ✉♥❞❡rst❛♥❞ ❤♦✇ t❤❡s❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s ❢♦r♠ ✐♥ ♦✉r ♠♦❞❡❧ ✇❡

♣r♦♣♦s❡ t♦ ❡①❛♠✐♥❡ ✐♥ ❞❡t❛✐❧s ❛♥ ■❇▼ s✐♠✉❧❛t✐♦♥ t❤r♦✉❣❤ ♣❛tt❡r♥ ♦❜s❡r✈❛t✐♦♥ ❛♥❞

♠❡❛s✉r✐♥❣ s♣❛t✐❛❧ ♠♦♠❡♥ts✳ ❋✐❣✉r❡ ✼✳✺ s❤♦✇s t❤❡ s♥❛♣s❤♦ts ♦❢ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢

t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥✳ ❚❤❡ s✐♠✉❧❛t✐♦♥ ✐s ✐♥✐t✐❛t❡❞ ✇✐t❤ n0 = 100 ✐♥❞✐✈✐❞✉❛❧s

❞✐str✐❜✉t❡❞ ✉♥✐❢♦r♠❧②✳ ❚❤❡ ✐♥❞✐✈✐❞✉❛❧s ❞✐✈✐❞❡ ❛♥❞ ❞✐s♣❡rs❡ ❞✉❡ t♦ t❤❡ ❧❛r❣❡ ♠♦t✐❧✐t②

❦❡r♥❡❧✳ ❆s t❤❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐♥❝r❡❛s❡s ✐♥ t❤❡ s②st❡♠s t❤❡ ♠♦t✐❧✐t② ♦❢ t❤❡

✐♥❞✐✈✐❞✉❛❧s ❞❡❝r❡❛s❡s ♣r♦❣r❡ss✐✈❡❧② ❛♥❞ ❝♦❧♦♥✐❡s st❛rt t♦ ❢♦r♠✳ ❚❤❡ ❢♦r♠❛t✐♦♥ ♦❢

❝♦❧♦♥✐❡s ✐♥ ♥♦t ❞✉❡ t♦ t❤❡ t♦t❛❧ ✐♠♠♦❜✐❧✐③❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❜✉t r❛t❤❡r t♦ ❧♦❝❛❧

❡q✉✐❧✐❜r✐✉♠ ❜❡t✇❡❡♥ ❞✐✈✐s✐♦♥ ✇❤✐❝❤ t❡♥❞ t♦ ♣r♦♠♦t❡ t❤❡ ❧♦❝❛❧ ❛❝❝✉♠✉❧❛t✐♦♥ ❞✉❡ t♦

t❤❡ s♠❛❧❧ ❜✐rt❤ ❦❡r♥❡❧ ✭wb = 3✮ ❛♥❞ ♠♦t✐❧✐t② t❤❛t t❡♥❞s t♦ ❞✐s♣❡rs❡ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳

❋✐❣✉r❡ ✼✳✽ r❡♣♦rts t❤❡ t✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞

s❤♦✇s ❛ r❛♣✐❞ ✜rst ♣❤❛s❡ ✇❤❡r❡ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ✐♥❝r❡❛s❡s ❜❡❢♦r❡ ❞❡❝r❡❛s✐♥❣

t♦✇❛r❞s ❛♥ ❡q✉✐❧✐❜r✐✉♠ ✈❛❧✉❡ (0.25)✳ ❚❤❡ ❡q✉✐❧✐❜r✐✉♠ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s

②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ✐s ❧♦✇❡r t❤❛♥ t❤❡ ✈❛❧✉❡ ❝❛❧❝✉❧❛t❡❞ ✉s✐♥❣ t❤❡ ♠❡❛♥✲✜❡❧❞ ♠♦❞❡❧

(0.35) ✐♥❞✐❝❛t✐♥❣ t❤❛t t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐♥ ❛✈❡r❛❣❡ ❞❡t❛❝❤ ❛t ❛ ❤✐❣❤❡r r❛t❡ t❤❛♥ ✇❤❛t

✇♦✉❧❞ ❜❡ ❡①♣❡❝t❡❞ ✐♥ t❤❡ ❛❜s❡♥❝❡ ♦❢ ❛♥② s♣❛t✐❛❧ ♣❛tt❡r♥✳

✼✳✸ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧

❲❡ ❞❡r✐✈❡ t❤❡ ❞②♥❛♠✐❝❛❧ ❡q✉❛t✐♦♥s ♦❢ t❤❡ ✜rst s♣❛t✐❛❧ ♠♦♠❡♥t ✭❛✈❡r❛❣❡ ❞❡♥s✐t②

♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✮ ❛♥❞ t❤❡ s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦♠❡♥t ✭♣❛✐r ❞❡♥s✐t② ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝✲

t✐♦♥✮ ❛♣♣r♦①✐♠❛t✐♥❣ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ■❇▼✳ ❚❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ✜rst ♠♦♠❡♥t ✐s

✐♥✢✉❡♥❝❡❞ ❜② ❞✐✈✐s✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t ❡✈❡♥ts✳ ❚❤❡ ♠♦t✐❧✐t② ♦❢ ❛♥ ✐♥❞✐✈✐❞✉❛❧ ❢r♦♠ ❛

❧♦❝❛t✐♦♥ x t♦ ❛ ❧♦❝❛t✐♦♥ x′ ❤❛s ♥♦ ✐♠♣❛❝t ♦♥ t❤❡ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤❡

❞②♥❛♠✐❝ ♦❢ t❤❡ ✜rst ♠♦♠❡♥t ✐s ❣✐✈❡♥ ❜②✿

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✼✳✸✳ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✶✷✶

✭❛✮ b1 = 0.10 ✭❜✮ b1 = 0.13

✭❝✮ b1 = 0.15

❋✐❣✉r❡ ✼✳✷✿ ❊①❛♠♣❧❡s ♦❢ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ❛♥❞ t❤❡ ■❇▼ ✇✐t❤

❡①tr❛❝❡❧❧✉❧❛r ♣r♦❞✉❝t

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✶✷✷

❈❤❛♣t❡r ✼✳ ❊①♣❧♦r✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s ✐♥ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢

❛ ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡ ❜❛❝t❡r✐❛

✭❛✮ m2 = 3.0 ✭❜✮ m2 = 2.0

✭❝✮ m2 = 4.0

❋✐❣✉r❡ ✼✳✸✿ ❊①❛♠♣❧❡s ♦❢ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ s✐♠♣❧✐✜❡❞ ■❇▼ ❛♥❞ t❤❡ ■❇▼ ✇✐t❤

❡①tr❛❝❡❧❧✉❧❛r ♣r♦❞✉❝t

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✼✳✸✳ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✶✷✸

✭❛✮ ✭❜✮

✭❝✮

❋✐❣✉r❡ ✼✳✹✿ P❛tt❡r♥ ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ✇✐t❤ ♣r♦❞✉❝t ❞②♥❛♠✐❝ ✭❜❛❝t❡r✐❛✿ r❡❞ ❛♥❞

♣♦❧②♠❡r✐❝ ♣❛rt✐❝❧❡s✿ ❜❧✉❡✮

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✶✷✹

❈❤❛♣t❡r ✼✳ ❊①♣❧♦r✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s ✐♥ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢

❛ ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡ ❜❛❝t❡r✐❛

✭❛✮ t = 0 ✭❜✮ t = 20

✭❝✮ t = 40 ✭❞✮ t = 60

✭❡✮ t = 80 ✭❢✮ t = 740

❋✐❣✉r❡ ✼✳✺✿ ❙♥❛♣s❤♦ts ♦❢ t❤❡ s♣❛t✐❛❧ ♣❛tt❡r♥ ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼ ❛t ❞✐✛❡r❡♥t t✐♠❡s✳

❚❤❡ ♣❛r❛♠❡t❡rs ❛r❡ b1 = 0.15✱ wb = 3✱ wd = 19✱ wm = 31✱ wv = 19✱ m1 = 1.0 ❛♥❞

m2 = 3.0

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✼✳✸✳ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✶✷✺

✭❛✮ t = 40

✭❜✮ t = 80

✭❝✮ t = 740

❋✐❣✉r❡ ✼✳✻✿ ❚✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ ❝❛rt❡s✐❛♥ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✳ ❚❤❡ ♣❛r❛♠❡✲

t❡rs ❛r❡ b1 = 0.15✱ wb = 3✱ wd = 19✱ wm = 31✱ wv = 19✱ m1 = 1.0 ❛♥❞ m2 = 3.0

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✶✷✻

❈❤❛♣t❡r ✼✳ ❊①♣❧♦r✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s ✐♥ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢

❛ ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡ ❜❛❝t❡r✐❛

✭❛✮ t = 40

✭❜✮ t = 80

✭❝✮ t = 740

❋✐❣✉r❡ ✼✳✼✿ ❚✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ t❤❡ ✬r❛❞✐❛❧✬ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✳ ❚❤❡ ♣❛r❛♠❡t❡rs

❛r❡ b1 = 0.15✱ wb = 3✱ wd = 19✱ wm = 31✱ wv = 19✱ m1 = 1.0 ❛♥❞ m2 = 3.0

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✼✳✸✳ ❉❡r✐✈✐♥❣ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ♠♦❞❡❧ ✶✷✼

❋✐❣✉r❡ ✼✳✽✿ ❚✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ ❛✈❡r❛❣❡ ❞❡♥s✐t② ♦❢ ✐♥❞✐✈✐❞✉❛❧ N

dN

dt= b1N − d1N − d′1

C(ξ)K

(

||ξ||

wd

)

dξ ✭✼✳✺✮

◆♦t❡ t❤❛t t❤❡ ♠♦t✐❧✐t② ✐s ♥♦t ✐♥✈♦❧✈❡❞ ✐♥ ❡q✉❛t✐♦♥ ✼✳✺ ❛s t❤❡ ♠♦t✐❧✐t② ♦❢ ❛♥ ✐♥❞✐✲

✈✐❞✉❛❧ ❢r♦♠ ♦♥❡ ♣♦s✐t✐♦♥ t♦ ❛♥♦t❤❡r ❞♦❡s ♥♦t ❛✛❡❝t t❤❡ t♦t❛❧ ♥✉♠❜❡r ♦❢ ✐♥❞✐✈✐❞✉❛❧s✳

❍♦✇❡✈❡r✱ ♠♦t✐❧✐t② ♠❛② ❛✛❡❝ts t❤❡ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✐♥❞✐r❡❝t❧② ❜② ♠♦❞✲

✐❢②✐♥❣ t❤❡ s♣❛t✐❛❧ ❞✐str✐❜✉t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛♥❞ ❝♦♥s❡q✉❡♥t❧② t❤❡✐r ❞❡t❛❝❤♠❡♥t

r❛t❡s✳

❚❤❡ s❡❝♦♥❞ ♠♦♠❡♥t ♠❡❛s✉r❡s t❤❡ ❞❡♥s✐t② ♦❢ ♣❛✐rs ♦❢ ✐♥❞✐✈✐❞✉❛❧s s❡♣❛r❛t❡❞ ✇✐t❤

❛ ✈❡❝t♦r✐❛❧ ❞✐st❛♥❝❡ ξ✳ ❚❤✐s ❞❡♥s✐t② ✐s ❛✛❡❝t❡❞ ❜② ❞✐✈✐s✐♦♥✱ ❞❡t❛❝❤♠❡♥t ❛♥❞ ♠♦t✐❧✐t②

❡✈❡♥ts✿

dC(ξ)

dt=

(

dC(ξ)

dt

)

division

+

(

dC(ξ)

dt

)

detachment

+

(

dC(ξ)

dt

)

motility

✭✼✳✻✮

❚❤❡ ✜rst t✇♦ t❡r♠s ♦♥ t❤❡ r✐❣❤t ❤❛♥❞ s✐❞❡ ❤❛✈❡ ❛❧r❡❛❞② ❜❡❡♥ ❞❡t❛✐❧❡❞ ✐♥ ❝❤❛♣t❡r

✹✳ ❚❤❡ ✜rst t❡r♠❡ ❛❝❝♦✉♥ts ❢♦r t❤❡ ♥❡t ✈❛r✐❛t✐♦♥ ♦❢ C(ξ) ❞✉❡ t♦ ❞✐✈✐s✐♦♥ ❡✈❡♥ts ✇❤✐❧❡

t❤❡ s❡❝♦♥❞ t❡r♠ ❛❝❝♦✉♥ts ❢♦r t❤❡ ♥❡t ✈❛r✐❛t✐♦♥ ♦❢ C(ξ) ❞✉❡ t♦ ❞❡t❛❝❤♠❡♥t ❡✈❡♥ts✳

❚❤❡ t❤✐r❞ t❡r♠ ✐♥ t❤❡ r✐❣❤t ❤❛♥❞ s✐❞❡ ♦❢ ❡q✉❛t✐♦♥ ✼✳✻ ❛❝❝♦✉♥ts ❢♦r t❤❡ ♥❡t ✈❛r✐❛t✐♦♥

♦❢ ❞❡♥s✐t② ♦❢ ♣❛✐rs ❛t ❞✐st❛♥❝❡ ξ✳ ❚❤✐s t❡r♠ ✐s ❣✐✈❡♥ ❜②✿

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✶✷✽

❈❤❛♣t❡r ✼✳ ❊①♣❧♦r✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s ✐♥ ❛ s✐♠♣❧✐✜❡❞ ■❇▼ ♦❢

❛ ♠✐❝r♦❜✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❡❞ ✇✐t❤ ♠♦t✐❧❡ ❜❛❝t❡r✐❛

(

dC(ξ)

dt

)

motility

= ✭✼✳✼✮

− m1C(ξ) +m2K

(

||ξ||

wv

)

C(ξ) ✭✼✳✽✮

+ m2

K

(

||ξ′′||

wv

)

T (ξ, ξ′′)dξ′′

+ m1

K

(

||ξ′||

wm

)

Cbb(ξ + ξ′)dξ′

− m2

∫ ∫

K

(

||ξ′||

wm

)

K

(

||ξ′′||

wv

)

T (ξ + ξ′, ξ′′)dξ′dξ′′

− m2

K

(

||ξ + ξ′||

wv

)

K

(

||ξ′||

wm

)

C(ξ + ξ′)dξ′

❚❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ✐s ❢♦r♠❡❞ ✇✐t❤ ✺ t❡r♠s✿

• t❤❡ ✜rst t❡r♠ ❞❡♥♦t❡s ❢♦r t❤❡ ♣❛✐rs ij ❧♦st ❞✉❡ t♦ t❤❡ ♠✐❣r❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧

i

• t❤❡ s❡❝♦♥❞ t❡r♠ ❝♦rr❡❝ts t❤❡ ✜rst t❡r♠ ❜② ❛❞❞✐♥❣ t❤❡ ❡✛❡❝t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧

j ✇✐t❤✐♥ t❤❡ ♣❛✐r ij ♦♥ t❤❡ ♠♦t✐❧✐t② ♣r♦❜❛❜✐❧✐t② ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i

• t❤❡ t❤✐r❞ t❡r♠ ❛❝❝♦✉♥ts ❢♦r t❤❡ ❡✛❡❝t ♦❢ ♥❡✐❣❤❜♦rs ♦❢ ❛ ❢♦❝❛❧ ✐♥❞✐✈✐❞✉❛❧ i ♦♥

t❤❡ ✐ts ♠♦t✐❧✐t② ♠♦t✐❧✐t② ♣r♦❜❛❜✐❧✐t②✳ ❚❤✐s ✐♠♣❧✐❡s t♦ ❝♦♥s✐❞❡r t❤❡ ❞❡♥s✐t② ♦❢

tr✐♣❧❡t ❢♦r♠❡❞ ✇✐t❤ t❤❡ ♣❛✐r ij ❛♥❞ ❛ ♥❡✐❣❤❜♦r k ❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ′′

• t❤❡ ❢♦✉rt❤ t❡r♠ ❛❝❝♦✉♥ts ❢♦r ♣❛✐rs ij ❝r❡❛t❡❞ ✇❤❡♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i ♦r✐❣✐♥❛❧❧②

❧♦❝❛t❡❞ ❛t ❛ ❞✐st❛♥❝❡ ξ + ξ′ ❢r♦♠ j ♠♦✈❡s ✇✐t❤ ❛ ❞✐st❛♥❝❡ −ξ′✳

• t❤❡ ✜❢t❤ t❡r♠ ❝♦rr❡❝ts t❤❡ ❢♦✉rt❤ t❡r♠ ❜② ✐♥❝❧✉❞✐♥❣ t❤❡ ❡✛❡❝t ♦❢ ♥❡✐❣❤❜♦rs ♦❢

i ✭♦t❤❡r t❤❛♥ t❤❡ ✐♥❞✐✈✐❞✉❛❧ j ♦♥ ✐ts ♠♦t✐❧✐t② ♣r♦❜❛❜✐❧✐t②

• ✜♥❛❧❧② t❤❡ s✐①t❤ t❡r♠ ❛❝❝♦✉♥t ❢♦r t❤❡ ❡✛❡❝t ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ j ✐♥ t❤❡ ♣❛✐r ij

❛t ❞✐st❛♥❝❡ ξ + ξ′ ♦♥ t❤❡ ♠♦t✐❧✐t② ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ i

❲❡ ❛tt❡♠♣t t♦ s♦❧✈❡ t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❛s ✐♥ t❤❡ ♣r❡✈✐♦✉s ❝❤❛♣t❡r ❜② ❞✐s❝r❡t✐③✐♥❣

t❤❡ ❞✐st❛♥❝❡s ξ ✇✐t❤ ❛ s♣❛t✐❛❧ st❡♣ dξ = (dξ1, dξ2) ❛♥❞ t✐♠❡ ✇✐t❤ ❛ ❝♦♥st❛♥t t✐♠❡st❡♣

∆t = 1 ✉s✐♥❣ ❛♥ ❡①♣❧✐❝✐t ❊✉❧❡r s❝❤❡♠❡✳ ❍♦✇❡✈❡r t❤❡ r❡s✉❧t❛♥t ❞✐s❝r❡t✐③❡❞ s②st❡♠

❞✐✈❡r❣❡❞ ❛❢t❡r ❢❡✇ st❡♣s✳ ❚❤❡ ❞❡❝r❡❛s❡ ♦❢ t❤❡ t✐♠❡ st❡♣ t♦ 0.1 ❛♥❞ t♦ 0.01 ❞✐❞ ♥♦t

♣r❡✈❡♥t t❤❡ ❞✐✈❡r❣❡♥❝❡ ♦❢ t❤❡ ❛❧❣♦r✐t❤♠ ♥♦r ❞✐❞ t❤❡ ✐♠♣❧❡♠❡♥t❛t✐♦♥ ♦❢ ❘✉♥❣❡✲❑✉tt❛

s❝❤❡♠❡ ✭❘❑✹✮✳ ❲❡ ♣r❡s✉♠❡ t❤❛t t❤❡ ❞✐✣❝✉❧t② ✐♥ s♦❧✈✐♥❣ t❤❡s❡ ❡q✉❛t✐♦♥ ✐s ❞✉❡ t♦ t❤❡

r❛♣✐❞ ❞②♥❛♠✐❝ ♦❢ t❤❡ ♠♦t✐❧✐t② ✐♥ ❝♦♠♣❛r✐s♦♥ t♦ ❞✐✈✐s✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t ❞②♥❛♠✐❝

❢r♦♠ ♦♥❡ s✐❞❡ ❛♥❞ t❤❡ ❞✐s❝r❡♣❛♥❝② ❜❡t✇❡❡♥ t❤❡ s❝❛❧❡ ♦✈❡r ✇❤✐❝❤ ♠♦t✐❧✐t② ❛♥❞ ❜✐rt❤

♦❝❝✉rs ♣❧❛②✳

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✼✳✹✳ ❉✐s❝✉ss✐♦♥ ❛♥❞ ❝♦♥❝❧✉s✐♦♥ ✶✷✾

✼✳✹ ❉✐s❝✉ss✐♦♥ ❛♥❞ ❝♦♥❝❧✉s✐♦♥

■♥ t❤✐s ❝❤❛♣t❡r ✇❡ s❤♦✇ t❤❛t t❤❡ s✐♠♣❧✐✜❝❛t✐♦♥ ♦❢ t❤❡ ♣♦❧②♠❡r ❞②♥❛♠✐❝ ✭■❇▼ ♦❢

❝❤❛♣t❡r ✻✮ st✐❧❧ ❛❧❧♦✇ t❤❡ ♦❜t❛✐♥♠❡♥t ♦❢ ❞✐✈❡rs✐t② ♦❢ ♣❛tt❡r♥s ✐♥❝❧✉❞✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲

❧✐❦❡ ♣❛tt❡r♥ t❤❛t ❤❛✈❡ ❜❡❡♥ ♦❜s❡r✈❡❞ ✐♥ ❧❛❜♦r❛t♦r② ❜✐♦✜❧♠ ❡①♣❡r✐♠❡♥ts✳ ■♥ ❛ s②st❡♠

❢♦r♠❡❞ ✇✐t❤ ❛ ❞❡♥s✐t②✲✐♥❞❡♣❡♥❞❡♥t ♠♦t✐❧❡ ❜❛❝t❡r✐❛✱ t❤❡ ✐♥❞✐✈✐❞✉❛❧s t❡♥❞ t♦ ❞✐s♣❡rs❡

❛♥❞ ♣r♦❞✉❝❡ ♥♦ s♣❛t✐❛❧ str✉❝t✉r❡✳ ❖✉r ♠♦❞❡❧ s✉❣❣❡st t❤❛t t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s

✐♥ s✉❝❤ s②st❡♠ ♠❛② r❡s✉❧t ❢r♦♠ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② r❡❞✉❝t✐♦♥ ♣r♦❝❡ss✳ ❚❤❡

s♣❛t✐❛❧ ♣❛tt❡r♥ ♦❢ t❤❡ ❝♦❧♦♥✐❡s s❡❡♠s t♦ ❜❡ ✐♥✢✉❡♥❝❡❞ ❜② ❧♦❝❛❧ ❡q✉✐❧✐❜r✐✉♠ ❜❡t✇❡❡♥

✐♥❞✐✈✐❞✉❛❧s ✬❡♥t❡r✐♥❣✬ t❤❡ ❝♦❧♦♥② t❤r♦✉❣❤ ♠✐❣r❛t✐♦♥ ♦r ❞✐✈✐s✐♦♥ ❛♥❞ ✐♥❞✐✈✐❞✉❛❧s ✬❧❡❛✈✲

✐♥❣✬ t❤❡ ❝♦❧♦♥② t❤r♦✉❣❤ ♠✐❣r❛t✐♦♥ ❛♥❞ ❞❡t❛❝❤♠❡♥t✳ ■♥ t❤❡ ❛❜s❡♥❝❡ ♦❢ ♠♦t✐❧✐t② t❤❡

②✐❡❧❞❡❞ ♣❛tt❡r♥ ✐s ❢♦r♠❡❞ ✇✐t❤ ✐s♦❧❛t❡❞ ❝♦❧♦♥②✳ ❍♦✇❡✈❡r ✇❤❡♥ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t

♠♦t✐❧✐t② ✐s ❝♦♥s✐❞❡r❡❞ t❤❡ ❝♦❧♦♥✐❡s ♠❛② ❝♦♥♥❡❝t ②✐❡❧❞✐♥❣ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥s✳

❚❤❡ ❞❡t❛❝❤♠❡♥t ❦❡r♥❡❧ s❡❡♠s t♦ ♣❧❛② ❛ r♦❧❡ ✐♥ ♠❛✐♥t❛✐♥✐♥❣ t❤❡ str✐♣s ♦❢ t❤❡ ❧❛❜②r✐♥t❤

s❡♣❛r❛t❡❞✳ ❚❤✐s str✉❝t✉r❡ ②✐❡❧❞❡❞ ❛ ❝❛rt❡s✐❛♥ ❝♦rr❡❧❛t✐♦♥ ♠❛tr✐① ✇✐t❤ ❛ ♣❡❛❦ ✐♥ t❤❡

❝❡♥t❡r ✭✐♥❞✐❝❛t✐♥❣ t❤❡ t❡♥❞❡♥❝② ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧ t♦ ❛❣❣r❡❣❛t❡ ❞✉❡ t♦ t❤❡ r❡❞✉❝t✐♦♥

♦❢ t❤❡✐r ♠♦t✐❧✐t②✮ ❛♥❞ ❛ ✇❛✈② str✉❝t✉r❡ ❞✉❡ t♦ t❤❡ ❧❛❜②r✐♥t❤✲❧✐❦❡ ♣❛tt❡r♥✳

❚❤❡r❡ ❛r❡ ❢❡✇ ❛tt❡♠♣ts ✐♥ t❤❡ ❧✐t❡r❛t✉r❡ ♦❢ ❛♣♣r♦①✐♠❛t✐♥❣ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞✲

❡❧s ✇✐t❤ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ♠♦t✐❧✐t② ✉s✐♥❣ ♠♦♠❡♥t ♠♦❞❡❧s✳ ▼✉rr❡❧❧ ❛♥❞ ▲❛✇

❬▼✉rr❡❧❧ ✷✵✵✵❪ ❛♣♣r♦①✐♠❛t❡❞ ❛♥ ■❇▼ ♦❢ ❇❡❡t❧❡s ♠✐❣r❛t✐♦♥ ✐♥ ❛ ❢r❛❣♠❡♥t❡❞ ✇♦♦❞❧❛♥❞✳

❚❤❡② ❝♦♥s✐❞❡r❡❞ ❛ ✜①❡❞ ❧❛♥❞s❝❛♣❡ ♣❛tt❡r♥ ❛♥❞ ❛ss✉♠❡❞ t❤❛t ❜❡❡t❧❡s ❛r❡ ❛ttr❛❝t❡❞

❜② t❤❡ ❧♦❝❛t✐♦♥s ❝♦rr❡s♣♦♥❞✐♥❣ t♦ ✇♦♦❞❧❛♥❞✳ ■♥ t❤❡✐r ♠♦❞❡❧✱ ▼✉rr❡❧❧ ❛♥❞ ▲❛✇ ❝♦♥✲

s✐❞❡r❡❞ ♦♥❧② t❤❡ ♠♦t✐❧✐t② ♣r♦❝❡ss✭♥♦ ❜✐rt❤ ❛♥❞ ❞❡❛t❤ ♣r♦❝❡ss❡s✮✳ ■♥ t❤❡✐r ♣❛♣❡r✱ t❤❡

s✐③❡ ♦❢ t❤❡ ♠✐❣r❛t✐♦♥ ❦❡r♥❡❧ ✇❛s r❡❧❛t✐✈❡❧② s♠❛❧❧ ❝♦♠♣❛r❡❞ t♦ t❤❡ s✐③❡ ♦❢ t❤❡ ❞♦♠❛✐♥✳

❚❤❡ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧ ✭t❤❡ ❡q✉✐✈❛❧❡♥t ♦❢ K(||ξ||/wv) ✐♥ ♦✉r ✇♦r❦✮ ✐s ♥♦t s♣❡❝✐✜❡❞

❡①♣❧✐❝✐t❧② ✐♥ t❤❡✐r ✇♦r❦ ❛s t❤❡② ❛ss✉♠❡❞ t❤❛t ✐♥t❡r❛❝t✐♦♥ ♦❝❝✉r ❡①❝❧✉s✐✈❡❧② ✇❤❡♥ ❛♥

✐♥❞✐✈✐❞✉❛❧ ❡♥t❡rs ❛ ✇♦♦❞❧❛♥❞ ♣❛t❝❤✳ ■♠♣❧✐❝✐t❧②✱ t❤❡② ❝♦♥s✐❞❡r ❛♥ ✐♥t❡r❛❝t✐♦♥ ❦❡r♥❡❧

✇✐t❤ ❛ s✐③❡ ❝♦rr❡s♣♦♥❞✐♥❣ t♦ t❤❡ s✐③❡ ♦❢ ❛ ♣❛t❝❤ ✭❡q✉✐✈❛❧❡♥t t♦ t❤❡ s♣❛t✐❛❧ r❡s♦❧✉t✐♦♥

dξ ✐♥ ♦✉r ✇♦r❦✮✳ ❚❤♦✉❣❤ s✐♠♣❧❡r t❤❛♥ ♦✉r ♠♦❞❡❧✱ ▼✉rr❡❧❧ ❛♥❞ ▲❛✇ ❤✐❣❤❧✐❣❤t❡❞

t❤❛t t❤❡r❡ ♠❛② ❜❡ ♣r❛❝t✐❝❛❧ ♣r♦❜❧❡♠s ✐♥ t❤❡ ♥✉♠❡r✐❝❛❧ ✐♥t❡❣r❛t✐♦♥ ♦❢ t❤❡ ❞②♥❛♠✐❝❛❧

s②st❡♠ ❞✉❡✱ ✐♥ t❤❡✐r ✇♦r❦✱ t♦ t❤❡ ❞✐s❝r❡♣❛♥❝② ❜❡t✇❡❡♥ t❤❡ s❝❛❧❡ ♦❢ ♠♦✈❡♠❡♥t ❛♥❞

t❤❡ s♣❛❝❡ s❝❛❧❡ ♦❢ t❤❡ ✇♦♦❞❧❛♥❞ ♣❛tt❡r♥s✳

■♥ t❤✐s ✇♦r❦ ✇❡ ♠❡❡t ❝♦♠♣❛r❛❜❧❡ ❞✐✣❝✉❧t✐❡s ✐♥ t❤❡ ♥✉♠❡r✐❝❛❧ ✐♥t❡❣r❛t✐♦♥ ♦❢ t❤❡

♠♦♠❡♥t ♠♦❞❡❧✳ ❲❡ ♣r❡s✉♠❡ t❤❛t ✐♥ ♣❛rt t❤❡ ✐♥st❛❜✐❧✐t② ♦❢ ♦✉r ♥✉♠❡r✐❝❛❧ s❝❤❡♠❡ ✐s

❞✉❡ t♦ t❤❡ ❞✐s❝r❡♣❛♥❝② ❜❡t✇❡❡♥ t❤❡ s♣❛t✐❛❧ s❝❛❧❡s ♦✈❡r ✇❤✐❝❤ t❤❡ ❞✐✛❡r❡♥t ♣r♦❝❡ss❡s

♦❝❝✉r ❝♦♠❜✐♥❡❞ ✇✐t❤ t❤❡ s✐❣♥✐✜❝❛♥t ❞✐✛❡r❡♥❝❡ ✐♥ t❤❡ ♠♦t✐❧✐t② r❛t❡ ❛♥❞ ❜✐rt❤ ❛♥❞

❞❡t❛❝❤♠❡♥t r❛t❡s✳ ❲❡ ❤♦♣❡ t♦ ❛❞❞r❡ss t❤❡s❡ ✐ss✉❡s ✐♥ ❛ ❢✉t✉r❡ ✇♦r❦✳

Page 143: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and
Page 144: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❈❤❛♣t❡r ✽

❈♦♥❝❧✉s✐♦♥

❈♦♥t❡♥ts

✽✳✶ P❡rs♣❡❝t✐✈❡s ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✳ ✶✸✸

❚❤✐s t❤❡s✐s t❛❦❡s ♣❧❛❝❡ ✐♥ t❤❡ ❝♦♥t❡①t ♦❢ t❤❡ ❞❡❜❛t❡ ❜❡t✇❡❡♥ ❝♦♠♣❧❡① ✐♥❞✐✈✐❞✉❛❧

❜❛s❡❞ ♠♦❞❡❧s ✭■❇▼s✮ ❛♥❞ ♠♦r❡ tr❛❞✐t✐♦♥❛❧ ❞✐✛❡r❡♥t✐❛❧ ❡q✉❛t✐♦♥ ♠♦❞❡❧s ✇✐t❤ ❛ ❧♦✇

♥✉♠❜❡r ♦❢ ✈❛r✐❛❜❧❡s✳ ❚❤❡ ✉s❡ ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧s ✭■❇▼s✮ ✐♥ ♠✐❝r♦❜✐❛❧ ❡❝♦❧✲

♦❣② ❤❛s ❜❡❡♥ ❣r♦✇✐♥❣ r❛♣✐❞❧② ❞✉r✐♥❣ t❤❡ ❧❛st t✇♦ ❞❡❝❛❞❡s✱ ❡♥❝♦✉r❛❣❡❞ ❜② t❤❡ ❢❛st

✐♥❝r❡❛s❡ ✐♥ ❝♦♠♣✉t✐♥❣ ♣♦✇❡r ❛♥❞ ❛❞✈❛♥❝❡s ✐♥ ❧❛❜♦r❛t♦r② ♦❜s❡r✈❛t✐♦♥ t❡❝❤♥✐q✉❡s✳

■❇▼s ❡①♣❛♥❞ t❤❡ t♦♦❧❜♦① ♦❢ t❤❡♦r❡t✐❝❛❧ ❡❝♦❧♦❣✐sts ♣r♦✈✐❞✐♥❣ ❛ ✈❛❧✉❛❜❧❡ ♠❡❛♥s t♦

✐♥✈❡st✐❣❛t❡ ❤♦✇ s②st❡♠✲❧❡✈❡❧ ♣r♦♣❡rt✐❡s ❡♠❡r❣❡ ♦✉t ♦❢ ❧♦❝❛❧ ✐♥t❡r❛❝t✐♦♥s✳ ❍♦✇❡✈❡r

s❡✈❡r❛❧ r❡✈✐❡✇s ❛♥❞ t❡①t❜♦♦❦s ♦♥ t❤❡ ✉s❡ ♦❢ ■❇▼s ✐♥ ❡❝♦❧♦❣② ✭❜✉t ❛❧s♦ ✐♥ ♦t❤❡r

✜❡❧❞s✮ ♣♦✐♥t❡❞ ♦✉t s♦♠❡ ♦❢ t❤❡ ❧✐♠✐t❛t✐♦♥ ♦❢ t❤❡ ❛♣♣r♦❛❝❤✳ ❚❤❡ ❝♦♠♣❧❡①✐t② ❛♥❞

❧✐♠✐t❡❞ ❣❡♥❡r❛❧✐t② ❛r❡ ♦❢t❡♥ q✉♦t❡❞ ❛s t❤❡ ♠❛✐♥ ❧✐♠✐t❛t✐♦♥s ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞✲

❡❧✐♥❣ ❬❯❝❤♠❛♥s❦✐ ✶✾✾✻❪ ❬●r✐♠♠ ✶✾✾✾❪✳ ■❇▼s ❡✈♦❧✈❡ ✐♥ ❛ ❧❛r❣❡ st❛t❡ s♣❛❝❡ ❛s t❤❡

❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ s②st❡♠ r❡q✉✐r❡s t❤❡ ❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ st❛t❡ ♦❢ ❛❧❧ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳

❆ ❦❡② q✉❡st✐♦♥ ✐s ✇❤❡t❤❡r ❛❧❧ t❤❡s❡ st❛t❡ ✈❛r✐❛❜❧❡s ❛r❡ ♥❡❝❡ss❛r② ❢♦r t❤❡ ♣✉r♣♦s❡ ♦❢

❛♥ ✐♥✈❡st✐❣❛t✐♦♥✳ ❆ s♠❛❧❧❡r ♠♦❞❡❧ ✇✐t❤ ❛ s♠❛❧❧ ♥✉♠❜❡r ♦❢ ❛❣❣r❡❣❛t❡❞ st❛t❡ ✈❛r✐❛❜❧❡s

✇♦✉❧❞♥✬t ❜❡ ♠♦r❡ ❛♣♣r♦♣r✐❛t❡ ❄

■♥ t❤✐s ✇♦r❦✱ ✇❡ tr② t♦ r❡❝♦♥❝✐❧❡ t❤❡s❡ ♦♣♣♦s✐t❡ ♣♦✐♥ts ♦❢ ✈✐❡✇✳ ■♥❞❡❡❞✱ ✇❡ ✐♥✈❡st✐✲

❣❛t❡ ❤♦✇ ♣r❛❝t✐❝❛❧ ❛♥❞ ♣r♦❞✉❝t✐✈❡ ✐t ✐s t♦ ❛♣♣r♦①✐♠❛t❡ t❤❡ ❞②♥❛♠✐❝ ♦❢ ■❇▼s ✉s❡❞ ✐♥

♠✐❝r♦❜✐❛❧ ❡❝♦❧♦❣② ✇✐t❤ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ✐♥✈♦❧✈✐♥❣ ❛ s♠❛❧❧ ♥✉♠❜❡r

♦❢ st❛t❡ ✈❛r✐❛❜❧❡s✳ ■♥ ♣❛rt✐❝✉❧❛r✱ ✇❡ ❛ss❡ss ✇❤❡t❤❡r t❤❡s❡ ✬s✐♠♣❧❡r✬ ♠♦❞❡❧s ❝❛♣t✉r❡

s✉❝❝❡ss❢✉❧❧② t❤❡ s♣❛t✐♦✲t❡♠♣♦r❛❧ ♣❛tt❡r♥s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼✳ ❙❡✈❡r❛❧ ❛❣❣r❡❣❛t❡❞

♠♦❞❡❧s ♦❢ t❤❡ ❧✐t❡r❛t✉r❡ ❞❡s❝r✐❜❡ ❝♦♠♣❧❡① ♠✐❝r♦❜✐❛❧ s②st❡♠s ✇✐t❤♦✉t r❡❢❡rr✐♥❣ ❡①✲

♣❧✐❝✐t❧② t♦ ✐♥❞✐✈✐❞✉❛❧s✱ ❛♥❞ ❛s ❛ ✜rst ❛♣♣r♦❛❝❤ ✇❡ ❝♦♠♣❛r❡ ✐♥ ❝❤❛♣t❡r ✷ ♦♥❡ ♦❢ t❤❡s❡

♠♦❞❡❧s ✭❛ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧✮ t♦ ❛♥ ■❇▼ ♦❢ ❜❛❝t❡r✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✳ ❚❤❡ ■❇▼

❡①♣❧✐❝✐t❧② r❡♣r❡s❡♥ts t❤❡ ✐♥❞✐✈✐❞✉❛❧ ♠✐❝r♦❜✐❛❧ ❝❡❧❧s ❛♥❞ t❤❡✐r ✈❛r✐❛❜✐❧✐t②✳ ❈♦♠♣❛r✲

✐s♦♥s ♦❢ t❤✐s t②♣❡ ❝❛♥ ❜❡ ❤❡❧♣❢✉❧ ❛s t❤❡ ❞❡t❡r♠✐♥✐st✐❝ ♠♦❞❡❧ ❝❛♥ ♣r♦✈✐❞❡ ✉s ✇✐t❤ ❛

r❡❢❡r❡♥❝❡ t♦ ✇❤✐❝❤ t❤❡ ■❇▼ r❡s✉❧ts ❝❛♥ ❜❡ ❝♦♠♣❛r❡❞✳ ❍♦✇❡✈❡r✱ ✇❡ s❤♦✇ t❤❛t t❤❡

❝♦♠♣❛r✐s♦♥ ❝❛♥ ❜❡ ❞✐✣❝✉❧t ✭❡✈❡♥ ♠❡❛♥✐♥❣❧❡ss✮ ✇❤❡♥ t❤❡ ❛❣❣r❡❣❛t❡❞ ♠♦❞❡❧ ✐s ❞❡✲

r✐✈❡❞ ✐♥❞❡♣❡♥❞❡♥t❧② ♦❢ t❤❡ ■❇▼✳ ❖♥❡ ♦❢ t❤❡ ♠❛✐♥ ❞✐✣❝✉❧t✐❡s ✐s t♦ ❛ss✐❣♥ ❛♣♣r♦♣r✐❛t❡

✈❛❧✉❡s t♦ t❤❡ ♣❛r❛♠❡t❡rs ♦❢ ❜♦t❤ ♠♦❞❡❧s✱ ❡s♣❡❝✐❛❧❧② ✇❤❡♥ s♦♠❡ ♦❢ t❤❡s❡ ♣❛r❛♠❡t❡rs

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✶✸✷ ❈❤❛♣t❡r ✽✳ ❈♦♥❝❧✉s✐♦♥

❤❛✈❡ ♥♦ ❝❧❡❛r ♣❤②s✐❝❛❧ ♠❡❛♥✐♥❣✳ ■♥ ♦✉r ❡①❛♠♣❧❡✱ ✇❡ ❤❛❞ t♦ t✉♥❡ t❤❡ ♣❛r❛♠❡t❡rs ♦❢

t❤❡ ❞✐✛✉s✐♦♥✲r❡❛❝t✐♦♥ ♠♦❞❡❧ ❡♠♣✐r✐❝❛❧❧② t♦ ♦❜t❛✐♥ t❤❡ ❜❡st ✜t ✇✐t❤ t❤❡ ■❇▼✳

❚❤❡♥ ✇❡ ❛❞♦♣t❡❞ ❛ ❣❡♥❡r❛❧ ❛♣♣r♦❛❝❤ ✐♥✈♦❧✈✐♥❣ t✇♦ st❡♣s✿ ✭✐✮ s✐♠♣❧✐❢②✐♥❣ ■❇▼s

t♦ tr❛♥s❢♦r♠ t❤❡♠ ✐♥t♦ ❝❧❡❛r❡r ♠❛t❤❡♠❛t✐❝❛❧ ♦❜❥❡❝ts ❛♥❞ ✭✐✐✮ ❞❡r✐✈✐♥❣ ❞❡t❡r♠✐♥✲

✐st✐❝ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s ✇❤✐❝❤ ❛♣♣r♦①✐♠❛t❡ s♦♠❡ ❛❣❣r❡❣❛t❡❞ ❞②♥❛♠✐❝s ♦❢ t❤✐s

s✐♠♣❧✐✜❡❞ ■❇▼✳ ❲❡ ❢♦❝✉s❡❞ ♦♥ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ t❡❝❤♥✐q✉❡s ✇❤✐❝❤ ♣r♦✈✐❞❡ ❛

✈❛❧✉❛❜❧❡ ♠❡❛♥s t♦ ❞❡r✐✈❡ ❞❡t❡r♠✐♥✐st✐❝ ♠♦❞❡❧s ♦♥ t❤❡ ♠✐❞❞❧❡ ❣r♦✉♥❞ ❜❡t✇❡❡♥ ♦✈❡r✲

s✐♠♣❧✐✜❡❞ ♠❡❛♥✲✜❡❧❞ ♠♦❞❡❧s ❛♥❞ ✐♥tr❛❝t❛❜❧❡ ■❇▼s✳ ■♥ ♣❛rt✐❝✉❧❛r✱ t❤✐s ❛♣♣r♦❛❝❤

❛❧❧♦✇s ♦♥❡ t♦ ❝❛♣t✉r❡ s♦♠❡ ✐♠♣♦rt❛♥t ❛s♣❡❝ts ♦❢ s♣❛t✐❛❧ ❞②♥❛♠✐❝s✳ ❈❤❛♣t❡r ✸ ❛♥❞

✹ ✐❧❧✉str❛t❡❞ ❤♦✇ s✉❝❤ ♠♦❞❡❧s ❛r❡ ❞❡r✐✈❡❞ ♦♥ t❤❡ ❡①❛♠♣❧❡ ♦❢ t❤❡ ❝♦❧♦♥② ❣r♦✇t❤ ❛♥❞

♣❧❛♥❛r ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t✳ ❚❤❡ ♠♦♠❡♥t ❛♣♣r♦❛❝❤ ❝❛♣t✉r❡s t❤❡ ♠❛✐♥ ❢❡❛t✉r❡s ♦❢

s♣❛t✐❛❧ ♣❛tt❡r♥ ❞②♥❛♠✐❝s ②✐❡❧❞❡❞ ❜② t❤❡ ■❇▼✳ ❚❤❡ ♦r✐❣✐♥❛❧✐t② ♦❢ t❤❡ ♠♦♠❡♥t ❛♣✲

♣r♦❛❝❤ ✐s ✐♥ ♣r♦❥❡❝t✐♥❣ t❤❡ ❝♦♠♣❧❡①✐t② ♦❢ t❤❡ ■❇▼ ✐♥t♦ ❛ ♥❡✇ st❛t❡ s♣❛❝❡ ✇❤❡r❡

t❤❡ ✈❛r✐❛❜❧❡s ❛r❡ t❤❡ ❛✈❡r❛❣❡ ♥✉♠❜❡r ♦❢ ✐♥❞✐✈✐❞✉❛❧s ✭✜rst s♣❛t✐❛❧ ♠♦♠❡♥t✮ ❛♥❞ t❤❡

❛✈❡r❛❣❡ ♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ❛t ❞✐✛❡r❡♥t ❞✐st❛♥❝❡s ✭s❡❝♦♥❞ s♣❛t✐❛❧ ♠♦✲

♠❡♥t ❣✐✈❡♥ ❜② t❤❡ ♣❛✐r ❝♦rr❡❧❛t✐♦♥ ❢✉♥❝t✐♦♥✮✳ ❚❤❡ ❤❡t❡r♦❣❡♥❡✐t✐❡s ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧

♣r♦♣❡rt✐❡s ✭♠❛ss ❛♥❞ ❞✐❛♠❡t❡r✮ ❛♥❞ t❤❡✐r s♣❛t✐❛❧ ❡①t❡♥t ❛r❡ ♥♦t ❝♦♥s✐❞❡r❡❞ ❜② t❤❡

♠♦♠❡♥t ♠♦❞❡❧✳ ❚❤❡ ♥✉tr✐❡♥t ❞②♥❛♠✐❝ ✐s ❛❧s♦ s✐♠♣❧✐✜❡❞ ❛♥❞ ❝♦♥s✐❞❡r❡❞ ✐♥❞✐r❡❝t❧②

t❤r♦✉❣❤ ❞❡♥s✐t②✲❞❡♣❡♥❞❡♥t ❣r♦✇t❤ ❢✉♥❝t✐♦♥ ✭❝❤❛♣t❡r ✸✮✳ ❚❤❡s❡ s✉❜st❛♥t✐❛❧ s✐♠♣❧✐✲

✜❝❛t✐♦♥s ♦❢ t❤❡ ♦r✐❣✐♥❛❧ ■❇▼ t❤❛t ❞✐❞ ♥♦t ♣r❡✈❡♥t t❤❡ ♠♦♠❡♥t ♠♦❞❡❧ t♦ r❡♣r♦❞✉❝❡

t❤❡ ♠❛✐♥ st❛t✐st✐❝❛❧ ❢❡❛t✉r❡s ♦❢ t❤❡ ■❇▼ s✐♠✉❧❛t✐♦♥✳

■♥ t❤❡ s❡❝♦♥❞ ♣❛rt ♦❢ t❤✐s t❤❡s✐s ✭❝❤❛♣t❡r ✺ t♦ ✼✮ ✇❡ ✐♥✈❡st✐❣❛t❡ ❤♦✇ t❤❡ ❢✉❧❧

❛♣♣r♦❛❝❤ ❛♣♣❧✐❡s t♦ ❛ ♥❡✇ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ ❢♦r♠❛t✐♦♥ ✐♥✈♦❧✈✐♥❣

♠♦t✐❧❡ ❜❛❝t❡r✐❛✱ ✇❤✐❝❤ ♠♦t✐❧✐t② ✐s r❡❞✉❝❡❞ ❜② ❛ s❡❧❢✲❡①❝r❡t❡❞ ♣r♦❞✉❝t ✭❡①♦♣♦❧②♠❡r✐❝

s✉❜st❛♥❝❡s✮✳ ❚❤❡ ■❇▼ ❛tt❡♠♣ts t♦ ❡①♣❧❛✐♥ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ♣❛tt❡r♥s ✇✐t❤ ✐♥t❡r✲

❝♦♥♥❡❝t❡❞ ♠✐❝r♦❝♦❧♦♥✐❡s ♦❜s❡r✈❡❞ ✐♥ r❡❝❡♥t ❜✐♦✜❧♠ ❡①♣❡r✐♠❡♥ts✳ ❈❤❛♣t❡r ✺ ❣✐✈❡s ❛

❞❡t❛✐❧❡❞ ❞❡s❝r✐♣t✐♦♥ ♦❢ t❤❡ ■❇▼ ❛♥❞ q✉❛❧✐t❛t✐✈❡ ❝♦♠♣❛r✐s♦♥ ♦❢ t❤❡ s✐♠✉❧❛t❡❞ ♣❛tt❡r♥s

✇✐t❤ t❤♦s❡ ♦❜s❡r✈❡❞ ✐♥ ❡①♣❡r✐♠❡♥t❛❧ ❧❛❜♦r❛t♦r② s❡tt✐♥❣ ♦❢ P✳ ❛❡r✉❣✐♥♦s❛ ❝✉❧t✐✈❛t✐♦♥✳✱

❛ ♠♦❞❡❧ ❜❛❝t❡r✐✉♠ ✐♥ ❜✐♦✜❧♠ r❡s❡❛r❝❤✳ ■♥ t❤✐s ♣❛rt✱ t❤❡ ♠♦♠❡♥t ❛♣♣r♦❛❝❤ ♣r♦✈✐❞❡❞

s♦♠❡ ✐♥t❡r❡st✐♥❣ ✐♥s✐❣❤ts ♦♥ t❤❡ st✉❞✐❡❞ ❞②♥❛♠✐❝s✱ ❜✉t ✇❡ ❛❧s♦ ❡♥❝♦✉♥t❡r❡❞ s♦♠❡ ♦❢

✐ts ❧✐♠✐t❛t✐♦♥s ❛♥❞ ❛❧s♦ s♦♠❡ ♣r❛❝t✐❝❛❧ ❞✐✣❝✉❧t✐❡s ♦❢ ✐♠♣❧❡♠❡♥t❛t✐♦♥✳

■♥ ❝❤❛♣t❡r ✻ ✇❡ ♣r♦♣♦s❡❞ ❛ s✐♠♣❧✐✜❡❞ ✈❡rs✐♦♥ ♦❢ t❤❡ ■❇▼ ♦❜t❛✐♥❡❞ ❜② ♥❡❣❧❡❝t✐♥❣

t❤❡ s♣❛t✐❛❧ ❡①t❡♥t ♦❢ t❤❡ ❜❛❝t❡r✐❛ ❛♥❞ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ♥✉tr✐❡♥t✳ ❚❤❡ ❡①❝r❡t✐♦♥ ♦❢

❡①tr❛❝❡❧❧✉❧❛r ♣r♦❞✉❝t ✐s ❝♦♥s✐❞❡r❡❞ ✐♥ t❤✐s ✜rst s✐♠♣❧✐✜❡❞ ♠♦❞❡❧✳ ❲❡ ❛♣♣r♦①✐♠❛t❡❞

t❤❡ r❡s✉❧t❛♥t ■❇▼ ✉s✐♥❣ ♠♦♠❡♥t ❛♣♣r♦❛❝❤ ❛♥❞ ❝♦♠♣❛r❡❞ t❤❡ ♣❛tt❡r♥s ❞②♥❛♠✐❝s

②✐❡❧❞❡❞ ❜② ❜♦t❤ ♠♦❞❡❧s✳ ❚❤❡ ♠♦♠❡♥t ♠♦❞❡❧ ❝❛♣t✉r❡❞ t❤❡ ❞②♥❛♠✐❝ ♦❢ t❤❡ ■❇▼ ✐♥

t❤❡ ❝❛s❡ ♦❢ ✐♠♠♦t✐❧❡ ❜❛❝t❡r✐❛ ❜✉t ❢❛✐❧❡❞ ✐♥ ❝❛♣t✉r✐♥❣ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ❝♦❧♦♥✐❡s ❛♥❞

t❤❡ s✉❜s❡q✉❡♥t r❡s✉❧t❛♥t tr❛♥s❢♦r♠❛t✐♦♥ ♦❢ t❤❡ ♣❛tt❡r♥s✳ ❚❤❡ ❞❡t❛✐❧❡❞ ❛♥❛❧②s✐s ♦❢

t❤❡ ■❇▼ ♣❛tt❡r♥s s❤♦✇s t❤❛t t❤❡ ❝♦❧♦♥✐❡s ❢♦r♠ ✇❤❡♥ t❤❡ ❧♦❝❛❧ ❞❡♥s✐t② ♦❢ ♣♦❧②♠❡r

r❡❛❝❤❡s ❛ t❤r❡s❤♦❧❞ ✈❛❧✉❡ ❝❛✉s✐♥❣ t❤❡ q✉❛s✐ ✐♠♠♦❜✐❧✐③❛t✐♦♥ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s✳ ❚❤✐s

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✽✳✶✳ P❡rs♣❡❝t✐✈❡s ✶✸✸

♠❛② ❤❛♣♣❡♥s ✐♥ ❢❡✇ ❧♦❝❛t✐♦♥ ✇✐t❤✐♥ t❤❡ ❞♦♠❛✐♥ ❞✉❡ t♦ t❤❡ st♦❝❤❛st✐❝ ✢✉❝t✉❛t✐♦♥s

♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ♥❡✐❣❤❜♦r❤♦♦❞ ❜✉t ♥♦t ♥❡❝❡ss❛r② ✐♥ ❛✈❡r❛❣❡✳ ❆s t❤❡ ♠♦♠❡♥t

♠♦❞❡❧ ✐s ❜❛s❡❞ ♦♥ t❤❡ ❛✈❡r❛❣❡ ♥❡✐❣❤❜♦r❤♦♦❞ ✐t ♠✐ss❡s t❤✐s ♣r♦❝❡ss✳ ❚❤❡ ❡①❛♠♣❧❡

✐❧❧✉str❛t❡s ✇❡❧❧ ♦♥❡ ♦❢ t❤❡ ♠❛❥♦r ❧✐♠✐t❛t✐♦♥ ♦❢ t❤❡ ♠♦♠❡♥t ❛♣♣r♦❛❝❤ ✐♥ ❞❡❛❧✐♥❣ ✇✐t❤

t❤❡ ✢✉❝t✉❛t✐♦♥s ❡s♣❡❝✐❛❧❧② ✐❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s r❡s♣♦♥s❡ t♦ t❤❡s❡ ✢✉❝t✉❛t✐♦♥s ❛r❡ ♥♦♥✲

❧✐♥❡❛r ♦r r✉❧❡❞ ❜② t❤r❡s❤♦❧❞ ✈❛❧✉❡s✳ ■♥ s✉❝❤ ❛ s✐t✉❛t✐♦♥ t❤❡ ❛❣❣r❡❣❛t✐♦♥ ♦❢ t❤❡ ■❇▼

✉s✐♥❣ ✜rst ❛♥❞ s❡❝♦♥❞ ♠♦♠❡♥t ♠❡❛s✉r❡s ❛s st❛t❡ ✈❛r✐❛❜❧❡ ♠❛② ♥♦t ❜❡ ❛♣♣r♦♣r✐❛t❡✳

❈❤❛♣t❡r ✼ ✐❧❧✉str❛t❡s s♦♠❡ ♦❢ t❤❡ t❡❝❤♥✐❝❛❧ ❧✐♠✐t❛t✐♦♥s t❤❛t ♠❛② ❜❡ ❡♥❝♦✉♥t❡r❡❞

✇❤❡♥ ✐♠♣❧❡♠❡♥t✐♥❣ ❛♥❞ s♦❧✈✐♥❣ ♠♦♠❡♥t ♠♦❞❡❧s✳ ❲❡ s✐♠♣❧✐❢② ❢✉rt❤❡r t❤❡ ■❇▼

✇✐t❤ ♠♦t✐❧❡ ❜❛❝t❡r✐❛ ❜② ❞r♦♣♣✐♥❣ t❤❡ ♣♦❧②♠❡r ❞②♥❛♠✐❝s ❛♥❞ ❛ss✉♠✐♥❣ t❤❛t t❤❡

❜❛❝t❡r✐❛ ♠♦t✐❧✐t② ✐s r❡❞✉❝❡❞ ❜② t❤❡ ✐♥❝r❡❛s❡ ♦❢ t❤❡✐r ❧♦❝❛❧ ❞❡♥s✐t②✳ ❚❤❡ r❡s✉❧t❛♥t

♠♦❞❡❧ ✐s s✐♠♣❧❡r t♦ ❛♥❛❧②③❡ t❤♦✉❣❤ ♥✉♠❡r✐❝❛❧ ❡①♣❡r✐♠❡♥t❛t✐♦♥ ❛♥❞ st✐❧❧ r❡♣r♦❞✉❝❡s

t❤❡ r✐❝❤ ♣❛tt❡r♥s t❤❛t ❝❛♥ ❜❡ ♦❜s❡r✈❡❞ ✇✐t❤ t❤❡ ♣♦❧②♠❡r✳ ❲❡ ❞✐s❝r❡t✐③❡❞ t❤❡ ♠♦♠❡♥t

♠♦❞❡❧ ✉s✐♥❣ ❡✐t❤❡r ❊✉❧❡r s❝❤❡♠❡ ❛♥❞ ❘❑✹ ❜✉t ❜♦t❤ t✐♠❡ ❞✐s❝r❡t✐③❛t✐♦♥ s❝❤❡♠❡s

❛r❡ ✉♥st❛❜❧❡ ❢♦r t❤❡ ♣❛r❛♠❡t❡rs t❤❛t ✇❡ ❝♦♥s✐❞❡r❡❞✳ ❚❤❡ ❞✐s❝r❡♣❛♥❝② ❜❡t✇❡❡♥ t❤❡

♠♦t✐❧✐t② ❛♥❞ ❜✐rt❤ ❦❡r♥❡❧ s✐③❡ ❛♥❞ t❤❡ s✐❣♥✐✜❝❛♥t ❞✐✛❡r❡♥❝❡ ❜❡t✇❡❡♥ t❤❡ t✐♠❡ s❝❛❧❡

❛♥❞ ♠♦❜✐❧✐t② ❛♥❞ t❤❡ ♦t❤❡r ♣r♦❝❡ss❡s ❛r❡ ♣r♦❜❛❜❧② ❛t t❤❡ ♦r✐❣✐♥ ♦❢ t❤❡s❡ ✐♥st❛❜✐❧✐t✐❡s✳

❲❡ s❤❛❧❧ ♥♦t❡ ❤♦✇❡✈❡r t❤❛t t❤❡ ♠♦♠❡♥t ❡q✉❛t✐♦♥s st✐❧❧ ♠✐ss ❛ s♦❧✐❞ ♠❛t❤❡♠❛t✐❝❛❧

❢r❛♠❡✇♦r❦ t❤❛t ❛❧❧♦✇ t❤❡ ❛♥❛❧②s✐s ♦❢ t❤❡✐r ♣r♦♣❡rt✐❡s✳

✽✳✶ P❡rs♣❡❝t✐✈❡s

❚❤❡ ❛❣❣r❡❣❛t✐♦♥ ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧s t❤❛t ❛r✐s❡ ✐♥ ❡❝♦❧♦❣②✱ ❛♥❞ ♠✐❝r♦❜✐❛❧

❡❝♦❧♦❣② ✐♥ ♣❛rt✐❝✉❧❛r✱ ✐s st✐❧❧ ✐♥ ✐ts ✐♥❢❛♥❝② ❛s ❛ r❡s❡❛r❝❤ ✜❡❧❞✳ ❚❤❡r❡ ❛r❡ ❢❡✇ ❛tt❡♠♣ts

✐♥ t❤❡ ♠✐❝r♦❜✐❛❧ ❡❝♦❧♦❣✐❝❛❧ ❧✐t❡r❛t✉r❡ t♦ s✐♠♣❧✐❢② t❤❡ ❞❡t❛✐❧❡❞ ■❇▼s ❛♥❞ ❛♣♣r♦①✐♠❛t❡

t❤❡✐r ❞②♥❛♠✐❝s ✉s✐♥❣ ❛ s♠❛❧❧ ♥✉♠❜❡r ♦❢ ❛❣❣r❡❣❛t❡❞ st❛t❡ ✈❛r✐❛❜❧❡s✳ ❚❤❡ ❛♣♣r♦❛❝❤

✐s ♠♦r❡ ❡♥❝♦✉♥t❡r❡❞ ✐♥ ♣❤②s✐❝s t❤r♦✉❣❤ t❤❡ ❞❡r✐✈❛t✐♦♥ ♦❢ t❤❡ ♠❛st❡r ❡q✉❛t✐♦♥ ❛♥❞

✐ts ❢✉rt❤❡r r❡❞✉❝t✐♦♥ t♦ s✐♠♣❧❡r ♠♦❞❡❧s✳ ❚❤❡ ❞✐✣❝✉❧t② t♦ ❡①t❡♥❞ t❤✐s ❛♣♣r♦❛❝❤ t♦

❡❝♦❧♦❣② ❧✐❡s ✐♥ t❤❡ r✐❝❤♥❡ss ❛♥❞ ❝♦♠♣❧❡①✐t② ♦❢ t❤❡ ❡❝♦❧♦❣✐❝❛❧ ✐♥t❡r❛❝t✐♦♥s✳ ▲✐✈✐♥❣

♦r❣❛♥✐s♠s✱ ✉♥❧✐❦❡ ✐♥❡rt ✐♥t❡r❛❝t✐♥❣ ♣❛rt✐❝❧❡s✱ ❤❛✈❡ t❤❡ ❝❛♣❛❝✐t② t♦ ❛❞❛♣t ❛♥❞ ❡✈♦❧✈❡

✇❤✐❝❤ ♠❛② ❝♦♥❢❡r t♦ t❤❡ ♣♦♣✉❧❛t✐♦♥ ♥❡✇ ❡♠❡r❣❡♥t ♣r♦♣❡rt✐❡s✳ ❲❡ ❜❡❧✐❡✈❡ t❤❛t ♠✉❝❤

r❡s❡❛r❝❤ ❡✛♦rt ❛r❡ st✐❧❧ ♥❡❡❞❡❞ t♦ ❞❡✈❡❧♦♣ r❡❧✐❛❜❧❡ t❡❝❤♥✐q✉❡s ❢♦r t❤❡ ❛❣❣r❡❣❛t✐♦♥ ❛♥❞

r❡❞✉❝t✐♦♥ ♦❢ ■❇▼s t❤❛t ❛r✐s❡ ✐♥ ❡❝♦❧♦❣②✳

▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥ ❝❛♥ ❜❡ ✉s❡❢✉❧ ✐♥ ❞❡r✐✈✐♥❣ ♥❡✇ ♠♦❞❡❧s ✇❤❡r❡ t❤❡ ❧♦❝❛❧

♥❡✐❣❤❜♦r❤♦♦❞ ♦❢ t❤❡ ✐♥❞✐✈✐❞✉❛❧s ✐s ❝♦♥s✐❞❡r❡❞ ❡①♣❧✐❝✐t❧② ❛s ❛ st❛t❡ ✈❛r✐❛❜❧❡✳ ❚❤❡②

❤♦✇❡✈❡r ❤❛✈❡ s♦♠❡ ❧✐♠✐t❛t✐♦♥s t❤❛t ♠❛② ❜❡ ♦✈❡r❝♦♠❡ ✇✐t❤ ❛♥ ❛❞❞✐t✐♦♥❛❧ r❡s❡❛r❝❤

❡✛♦rt✳ ■♥ ♣❛rt✐❝✉❧❛r t♦♦❧s ❛♥❞ ♠❡t❤♦❞s t♦ ❛♥❛❧②③❡ ♠♦♠❡♥t ♠♦❞❡❧s ❛r❡ ♥❡❡❞❡❞✳

❚❤❡r❡ ❛r❡ ♦t❤❡r t❡❝❤♥✐q✉❡s ❢♦r ❞❡r✐✈✐♥❣ ❛❣❣r❡❣❛t❡❞ ♠❛t❤❡♠❛t✐❝❛❧ ♠♦❞❡❧s t❤❛t ❝❛♥

❜❡ ❡①♣❧♦r❡❞ ✐♥ ❢✉t✉r❡ ✇♦r❦✳ ■♥ ♣❛rt✐❝✉❧❛r✱ ♠♦❞❡❧s ♦❢ ♣r♦❜❛❜✐❧✐t② ❞❡♥s✐t✐❡s ♣r♦✈✐❞❡

s♦♠❡ ❛✈❡r❛❣❡ ❜❡❤❛✈✐♦rs ✇❤✐❝❤ ❛r❡ ✐♥t❡r❡st✐♥❣ t♦ ❝♦♠♣❛r❡ ✇✐t❤ t❤❡ ❞✐✛❡r❡♥t r✉♥s ♦❢

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✶✸✹ ❈❤❛♣t❡r ✽✳ ❈♦♥❝❧✉s✐♦♥

t❤❡ ■❇▼✱ ❛♥❞ ❝❛♥ ❜❡ ❝♦♠♣❧❡♠❡♥t❛r② ✇✐t❤ t❤❡ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥✳ ■t ❝❛♥ ❛❧s♦

❜❡ ✐♥t❡r❡st✐♥❣ t♦ ❝♦♠♣✉t❡ t❤❡ s❡❝♦♥❞ ♠♦♠❡♥t ♦❢ t❤❡s❡ ❞❡♥s✐t② ♠♦❞❡❧s✱ ❛♥❞ ❝♦♠♣❛r❡

✐t ✇✐t❤ t❤❡ s❡❝♦♥❞ ♠♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥✳

❋✐♥❛❧❧② ■❇▼ s✐♠♣❧✐✜❝❛t✐♦♥ ♠❛② ②✐❡❧❞ ✑✉♥r❡❛❧✐st✐❝✑ ♠♦❞❡❧s ❜✉t ✐t s❡❡♠s t♦ ✉s ♥❡❝✲

❡ss❛r② ✐❢ ✇❡ ✇♦✉❧❞ ❧✐❦❡ t♦ ❣❡♥❡r❛❧✐③❡ t❤❡ ■❇▼ r❡s✉❧ts ❛♥❞ ❡❧❛❜♦r❛t❡ ♥❡✇ t❤❡♦r✐❡s✱ ❛♥❞

❡①♣❧♦r❡ ❤♦✇ ❝♦♠♣❧❡① str✉❝t✉r❡s ❝❛♥ ❡♠❡r❣❡ ❢♦r♠ ✐♥t❡r❛❝t✐♦♥s✳ ▼♦r❡♦✈❡r✱ ✇❡ ❤♦♣❡

t❤❛t ♦✉r ✇♦r❦ ❜r♦✉❣❤t s♦♠❡ ❝♦♥✈✐♥❝✐♥❣ ❡✈✐❞❡♥❝❡s t❤❛t ❞✐✛❡r❡♥t✐❛❧ ❡q✉❛t✐♦♥ ♠♦❞❡❧s

❛♣♣r♦①✐♠❛t✐♥❣ t❤❡s❡ ■❇▼s ❝❛♥ ❜r✐♥❣ s♦♠❡ ✐♥s✐❣❤t ❛❜♦✉t t❤✐s ♣r♦❝❡ss ♦❢ ❡♠❡r❣❡♥❝❡✳

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❇✐❜❧✐♦❣r❛♣❤②

❬❆❛s ✷✵✵✷❪ ❋✳ ❊✳ ❆❛s✱ ▼✳ ❲♦❧❢❣❛♥❣✱ ❙✳ ❋r②❡✱ ❙✳ ❉✉♥❤❛♠✱ ❈✳ ▲✈♦❧❞ ❛♥❞ ▼✳ ❑♦♦♠❡②✳

❈♦♠♣❡t❡♥❝❡ ❢♦r ♥❛t✉r❛❧ tr❛♥s❢♦r♠❛t✐♦♥ ✐♥ ◆❡✐ss❡r✐❛ ❣♦♥♦rr❤♦❡❛❡✿ ❝♦♠♣♦✲

♥❡♥ts ♦❢ ❉◆❆ ❜✐♥❞✐♥❣ ❛♥❞ ✉♣t❛❦❡ ❧✐♥❦❡❞ t♦ t②♣❡ ■❱ ♣✐❧✉s ❡①♣r❡ss✐♦♥✳ ▼♦❧❡❝✲

✉❧❛r ▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✹✻✱ ♥♦✳ ✸✱ ♣❛❣❡s ✼✹✾✕✼✻✵✱ ✷✵✵✷✳ ✻✽

❬❆❧❧❡s❡♥✲❍♦❧♠ ✷✵✵✻❪ ▼✳ ❆❧❧❡s❡♥✲❍♦❧♠✱ ❑✳ ❇✳ ❇❛r❦❡♥✱ ▲✳ ❨❛♥❣✱ ▼✳ ❑❧❛✉s❡♥✱ ❏✳ ❙✳

❲❡❜❜✱ ❙✳ ❑❥❡❧❧❡❜❡r❣✱ ❙✳ ▼♦❧✐♥✱ ▼✳ ●✐✈s❦♦✈ ❛♥❞ ❚✳ ❚♦❧❦❡r✲◆✐❡❧s❡♥✳ ❆ ❝❤❛r❛❝✲

t❡r✐③❛t✐♦♥ ♦❢ ❉◆❆ r❡❧❡❛s❡ ✐♥ Ps❡✉❞♦♠♦♥❛s ❛❡r✉❣✐♥♦s❛ ❝✉❧t✉r❡s ❛♥❞ ❜✐♦✜❧♠s✳

▼♦❧❡❝✉❧❛r ▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✺✾✱ ♥♦✳ ✹✱ ♣❛❣❡s ✶✶✶✹✕✶✶✷✽✱ ✷✵✵✻✳ ✻✽✱ ✼✾

❬❆❧♣❦✈✐st ✷✵✵✻❪ ❊✳ ❆❧♣❦✈✐st✱ ❈✳ P✐❝✐♦r❡❛♥✉✱ ▼✳❈✳▼✳ ❱❛♥ ▲♦♦s❞r❡❝❤t ❛♥❞ ❆✳ ❍❡②❞❡♥✳

❚❤r❡❡✲❞✐♠❡♥s✐♦♥❛❧ ❜✐♦✜❧♠ ♠♦❞❡❧ ✇✐t❤ ✐♥❞✐✈✐❞✉❛❧ ❝❡❧❧s ❛♥❞ ❝♦♥t✐♥✉✉♠ ❊P❙

♠❛tr✐①✳ ❇✐♦t❡❝❤♥♦❧♦❣② ❛♥❞ ❇✐♦❡♥❣✐♥❡❡r✐♥❣✱ ✈♦❧✳ ✾✹✱ ♣❛❣❡s ✾✻✶✕✾✼✾✱ ✷✵✵✻✳ ✼✾

❬❆❧♣❦✈✐st ✷✵✵✼❪ ❊✳ ❆❧♣❦✈✐st ❛♥❞ ■✳ ❑❧❛♣♣❡r✳ ❆ ♠✉❧t✐❞✐♠❡♥s✐♦♥❛❧ ♠✉❧t✐s♣❡❝✐❡s ❝♦♥t✐♥✲

✉✉♠ ♠♦❞❡❧ ❢♦r ❤❡t❡r♦❣❡♥✉♦✉s ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t✳ ❇✉❧❧❡t✐♥ ♦❢ ▼❛t❤❡♠❛t✐❝❛❧

❇✐♦❧♦❣②✱ ✈♦❧✳ ✻✾✱ ♣❛❣❡s ✼✻✺✕✼✽✾✱ ✷✵✵✼✳ ✶✷✱ ✶✸

❬❆rt❤✉r ✶✾✾✼❪ ❇✳ ❆rt❤✉r ❲✳✱ ◆✳ ❉✉r❧❛✉❢ ❙✳ ❛♥❞ ❆✳ ▲❛♥❡ ❉✳✱ ❡❞✐t❡✉rs✳ ❚❤❡ ❡❝♦♥♦♠②

❛s ❛♥ ❡✈♦❧✈✐♥❣ ❝♦♠♣❧❡① s②st❡♠ ✐✐✳ ❙❛♥t❛ ❋❡ ■♥st✐t✉t❡ ❙t✉❞✐❡s ✐♥ t❤❡ ❙❝✐❡♥❝❡

♦❢ ❈♦♠♣❧❡①✐t②✱ ❘❡❛❞✐♥❣s✱ ▼❆✿ ❆❞❞✐s♦♥✲❲❡s❧❡②✱ ✶✾✾✼✳ ✶

❬❆✉♠❛♥♥ ✷✵✵✼❪ ❈r❛✐❣ ❆✳ ❆✉♠❛♥♥✳ ❆ ♠❡t❤♦❞♦❧♦❣② ❢♦r ❞❡✈❡❧♦♣✐♥❣ s✐♠✉❧❛t✐♦♥ ♠♦❞❡❧s

♦❢ ❝♦♠♣❧❡① s②st❡♠s✳ ❊❝♦❧♦❣✐❝❛❧ ▼♦❞❡❧❧✐♥❣✱ ✈♦❧✳ ✷✵✷✱ ♥♦✳ ✸✲✹✱ ♣❛❣❡s ✸✽✺✕✸✾✻✱

❆♣r✐❧ ✷✵✵✼✳ ✶✱ ✹

❬❇❛r❦❡♥ ✷✵✵✽❪ ❑✳ ❇✳ ❇❛r❦❡♥✱ ❙✳ ❏✳ P❛♠♣✱ ▲✳❣ ❨❛♥❣✱ ▼✳ ●❥❡r♠❛♥s❡♥✱ ❏✳ ❏✳ ❇❡rtr❛♥❞✱

▼✳ ❑❧❛✉s❡♥✱ ▼✳❧ ●✐✈s❦♦✈✱ ❈✳ ❇✳ ❲❤✐t❝❤✉r❝❤✱ ❏✳ ◆✳ ❊♥❣❡❧ ❛♥❞ ❚✳ ❚♦❧❦❡r✲

◆✐❡❧s❡♥✳ ❘♦❧❡s ♦❢ t②♣❡ ■❱ ♣✐❧✐✱ ✢❛❣❡❧❧✉♠✲♠❡❞✐❛t❡❞ ♠♦t✐❧✐t② ❛♥❞ ❡①tr❛❝❡❧❧✉❧❛r

❉◆❆ ✐♥ t❤❡ ❢♦r♠❛t✐♦♥ ♦❢ ♠❛t✉r❡ ♠✉❧t✐❝❡❧❧✉❧❛r str✉❝t✉r❡s ✐♥ Ps❡✉❞♦♠♦♥❛s

❛❡r✉❣✐♥♦s❛ ❜✐♦✜❧♠s✳ ❊♥✈✐r♦♥♠❡♥t❛❧ ▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✶✵✱ ♥♦✳ ✾✱ ♣❛❣❡s ✷✸✸✶✕

✷✸✹✸✱ ✷✵✵✽✳ ✻✽✱ ✼✾✱ ✽✹

❬❇❡♥✲❏❛❝♦❜ ✷✵✵✵❪ ❊✳ ❇❡♥✲❏❛❝♦❜✱ ■✳ ❈♦❤❡♥ ❛♥❞ ❍✳ ▲❡✈✐♥❡✳ ❚❤❡ ❈♦♦♣❡r❛t✐✈❡ ❙❡❧❢✲

❖r❣❛♥✐③❛t✐♦♥ ♦❢ ▼✐❝r♦♦r❣❛♥✐s♠s✳ ❆❞✈✳ P❤②s✳✱ ✈♦❧✳ ✹✾✱ ♣❛❣❡s ✸✾✺✕✺✺✹✱ ✷✵✵✵✳

✶✷

❬❇✐r❝❤ ✷✵✵✻❪ ❆✳ ❇✐r❝❤ ❉✳ ❛♥❞ ❘✳ ❨♦✉♥❣ ❲✳ ❆ ♠❛st❡r ❡❛q✉❛t✐♦♥ ❢♦r ❛ s♣❛t✐❛❧ ♣♦♣✉✲

❧❛t✐♦♥ ♠♦❞❡❧ ✇✐t❤ ♣❛✐r ✐♥t❡r❛❝t✐♦♥s✳ ❚❤❡♦r❡t✐❝❛❧ P♦♣✉❧❛t✐♦♥ ❇✐♦❧♦❣②✱ ✈♦❧✳ ✼✵✱

♣❛❣❡s ✷✻✕✹✷✱ ✷✵✵✻✳ ✺✶✱ ✺✻

❬❇♦❧❦❡r ✶✾✾✼❪ ❇✳ ❇♦❧❦❡r ❛♥❞ ❙✳❲ ✳ P❛❝❛❧❛✳ ❯s✐♥❣ ▼♦♠❡♥t ❊q✉❛t✐♦♥s t♦ ❯♥❞❡rst❛♥❞

❙t♦❝❤❛st✐❝❛❧❧② ❉r✐✈❡♥ ❙♣❛t✐❛❧ P❛tt❡r♥ ❋♦r♠❛t✐♦♥ ✐♥ ❊❝♦❧♦❣✐❝❛❧ ❙②st❡♠s✳ ❚❤❡✲

♦r❡t✐❝❛❧ P♦♣✉❧❛t✐♦♥ ❇✐♦❧♦❣②✱ ✈♦❧✳ ✺✷✱ ♥♦✳ ✸✱ ♣❛❣❡s ✶✼✾✕✶✾✼✱ ❉❡❝❡♠❜❡r ✶✾✾✼✳

Page 149: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

✶✸✻ ❇✐❜❧✐♦❣r❛♣❤②

❬❇r❡❤♠✲❙t❡❝❤❡r ✷✵✵✹❪ ❇✳❋✳ ❇r❡❤♠✲❙t❡❝❤❡r ❛♥❞ ❊✳❆✳ ❏♦❤♥s♦♥✳ ❙✐♥❣❧❡✲❝❡❧❧ ♠✐❝r♦✲

❜✐♦❧♦❣②✿ t♦♦❧s✱ t❡❝❤♥♦❧♦❣✐❡s ❛♥❞ ❛♣♣❧✐❝❛t✐♦♥s✳ ▼✐❝r♦❜✐❛❧ ▼♦❧❡❝✉❧❛r ❇✐♦❧♦❣②

❘❡✈✐❡✇✱ ✈♦❧✳ ✻✽✱ ♣❛❣❡s ✺✸✽✕✺✺✾✱ ✷✵✵✹✳ ✹

❬❇✉r❡❧ ✷✵✵✸❪ ❋✳ ❇✉r❡❧ ❛♥❞ ❏✳ ❇❛✉❞r②✳ ▲❛♥❞s❝❛♣❡ ❡❝♦❧♦❣②✳ ❙❝✐❡♥❝❡ P✉❜❧✐s❤❡rs✱ ✷✵✵✸✳

✽✹

❬❇✉tt♦♥ ✶✾✾✸❪ ❉✳❑✳ ❇✉tt♦♥✳ ◆✉tr✐❡♥t✲❧✐♠✐t❡❞ ♠✐❝r♦❜✐❛❧ ❣r♦✇t❤ ❦✐♥❡t✐❝s✿ ♦✈❡r✈✐❡✇

❛♥❞ r❡❝❡♥t✳ ❆♥t♦♥✐❡ ✈❛♥ ▲❡❡✉✇❡♥❤♦❡❦✱ ✈♦❧✳ ✻✸✱ ♣❛❣❡s ✷✷✺✕✷✸✺✱ ✶✾✾✸✳ ✶✻

❬❈♦❣❛♥ ✷✵✵✹❪ ◆✳ ❈♦❣❛♥ ❛♥❞ ❏✳P✳ ❑❡❡♥❡r✳ ❚❤❡ r♦❧❡ ♦❢ t❤❡ ❜✐♦✜❧♠ ♠❛tr✐① ✐♥ str✉❝t✉r❛❧

❞❡✈❡❧♦♣♠❡♥t✳ ▼❛t❤✳ ▼❡❞✳ ❛♥❞ ❇✐♦❧✱ ✈♦❧✳ ✷✶✱ ♣❛❣❡s ✶✹✼✕✶✻✻✱ ✷✵✵✹✳ ✶✷✱ ✶✸

❬❈♦st❡rt♦♥ ✶✾✾✺❪ ❏❲ ❈♦st❡rt♦♥✱ ❩ ▲❡✇❛♥❞♦✇s❦✐✱ ❉❊ ❈❛❧❝✇❡❧❧✱ ❉❘ ❑♦r❜❡r ❛♥❞

❍▼ ▲❛♣♣✐♥✲❙❝♦tt✳ ▼✐❝r♦❜✐❛❧ ❜✐♦✜❧♠s✳ ❆♥♥✉ ❘❡✈ ▼✐❝r♦❜✐♦❧✱ ✈♦❧✳ ✹✾✱ ♣❛❣❡s

✼✶✶✕✼✹✺✱ ✶✾✾✺✳ ✶✷✱ ✻✽

❬❈r❛✇❢♦r❞ ✷✵✵✺❪ ❲✳ ❈r❛✇❢♦r❞ ❏✳✱ ❑✳ ❘✐t③ ❍❛rr✐s ❛♥❞ ▼✳ ❨♦✉♥❣ ■✳ ❚♦✇❛r❞s ❛♥

❡✈♦❧✉t✐♦♥♥❛r② ❡❝♦❧♦❣② ♦❢ ❧✐❢❡ ✐♥ s♦✐❧✳ ❚r❡♥❞s ❊❝♦❧✳ ❊✈♦❧✳✱ ✈♦❧✳ ✷✵✱ ♣❛❣❡s ✽✶✕✽✼✱

✷✵✵✺✳ ✶

❬❉❛❧t♦♥ ✶✾✾✹❪ ❍✳▼✳ ❉❛❧t♦♥✱ ▲✳❑✳ P♦✉❧s❡♥✱ P✳ ❍❛❧❛③✱ ▼✳▲✳ ❆♥❣❧❡s ❛♥❞ ❆✳❊✳ ●♦♦❞✲

♠❛♥✳ ❙✉❜str❛t✉♠✲✐♥❞✉❝❡❞ ♠♦r♣❤♦❧♦❣✐❝❛❧ ❝❤❛♥❣❡s ✐♥ ❛ ♠❛r✐♥❡ ❜❛❝t❡r✐✉♠ ❛♥❞

t❤❡✐r r❡❧❡✈❛♥❝❡ t♦ ❜✐♦✜❧♠ str✉❝t✉r❡✳ ❏♦✉r♥❛❧ ♦❢ ❇❛❝t❡r✐♦❧♦❣②✱ ✈♦❧✳ ✶✼✻✱ ♣❛❣❡s

✻✾✵✵✕✻✾✵✻✱ ✶✾✾✹✳ ✼✾

❬❉❛❧t♦♥ ✶✾✾✻❪ ❍ ▼ ❉❛❧t♦♥✱ ❆ ❊ ●♦♦❞♠❛♥ ❛♥❞ ❑ ❈ ▼❛rs❤❛❧❧✳ ❉✐✈❡rs✐t② ✐♥ s✉r❢❛❝❡

❝♦❧♦♥✐③❛t✐♦♥ ❜❡❤❛✈✐♦r ✐♥ ♠❛r✐♥❡ ❜❛❝t❡r✐❛✳ ❏♦✉r♥❛❧ ♦❢ ■♥❞✉str✐❛❧ ▼✐❝r♦❜✐♦❧♦❣②

❛♥❞ ❇✐♦t❡❝❤♥♦❧♦❣②✱ ✈♦❧✳ ✶✼✱ ♥♦✳ ✸✱ ♣❛❣❡s ✷✷✽✕✷✸✹✱ ❙❡♣t❡♠❜❡r ✶✾✾✻✳ ✼✾

❬❉❛✈❡② ✷✵✵✵❪ ▼✳❊✳ ❉❛✈❡② ❛♥❞ ●✳❆✳ ❖✬❚♦♦❧❡✳ ▼✐❝r♦❜✐❛❧ ❇✐♦✜❧♠s✿ ❢r♦♠ ❊❝♦❧♦❣② t♦

▼♦❧❡❝✉❧❛r ●❡♥❡t✐❝s✳ ▼✐❝r♦❜✐♦❧♦❣② ❆♥❞ ▼♦❧❡❝✉❧❛r ❇✐♦❧♦❣② ❘❡✈✐❡✇s✱ ✈♦❧✳ ✶✷✱

♣❛❣❡s ✽✹✼✕✽✻✼✱ ✷✵✵✵✳ ✻✽

❬❉❡✛✉❛♥t ✷✵✵✹❪ ●✳ ❉❡✛✉❛♥t✳ ▼♦❞❡❧✐s❡r ❧❛ ❝♦♠♣❧❡①✐t❡✿ q✉❡❧q✉❡s ♣✐st❡s ♣♦✉r r❡❧❡✈❡r

❧❡ ❞❡✜✳ ❘❛♣♣♦rt t❡❝❤♥✐q✉❡✱ ▼❡♠♦✐r❡ ❞✬❍❛❜✐❧✐t❛t✐♦♥ ❛ ❉✐r✐❣❡r ❞❡s ❘❡❝❤❡r❝❤❡s✳

❊❝♦❧❡ ❉♦❝t♦r❛❧❡ ❙P■✳ ❯♥✐✈❡rs✐t❡ ❇❧❛✐s❡ P❛s❝❛❧ ❞❡ ❈❧❡r♠♦♥t✲❋❡rr❛♥❞✱ ✷✵✵✹✳ ✶✱

❬❉❡✛✉❛♥t ✷✵✵✺❪ ●✳ ❉❡✛✉❛♥t✱ ❙✳ ❍✉❡t ❛♥❞ ❋✳ ❆♠❜❧❛r❞✳ ❆♥ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧

♦❢ ✐♥♥♦✈❛t✐♦♥ ❞✐✛✉s✐♦♥ ♠✐①✐♥❣ s♦❝✐❛❧ ✈❛❧✉❡ ❛♥❞ ✐♥❞✐✈✐❞✉❛❧ ❜❡♥❡✜t✳ ❆♠❡r✐✲

❝❛♥ ❏♦✉r♥❛❧ ♦❢ ❙♦❝✐♦❧♦❣② ✶✶✵✲✹✱ ✶✵✹✶✲✶✵✻✾✳ ❆♠❡r✐❝❛♥ ❏♦✉r♥❛❧ ♦❢ ❙♦❝✐♦❧♦❣②✱

✈♦❧✳ ✶✶✵✱ ♣❛❣❡s ✶✵✹✶✕✶✵✻✾✱ ✷✵✵✺✳ ✶

❬❉❡♥s ✷✵✵✺❪ ❊✳❏✳ ❉❡♥s✱ ❑✳ ❇❡r♥❛❡rts✱ ❆✳❘✳ ❙t❛♥❞❛❡rt✱ ❏✳❯✳ ❑r❡❢t ❛♥❞ ❏✳❋✳ ❱❛♥ ■♠♣❡✳

❈❡❧❧ ❞✐✈✐s✐♦♥ t❤❡♦r② ❛♥❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧❧✐♥❣ ♦❢ ♠✐❝r♦❜✐❛❧ ❧❛❣✳ P❛rt ■■✳

▼♦❞❡❧✐♥❣ ❧❛❣ ♣❤❡♥♦♠❡♥❛ ✐♥❞✉❝❡❞ ❜② t❡♠♣❡r❛t✉r❡ s❤✐❢ts✳ ❏♦✉r♥❛❧ ♦❢ ❋♦♦❞

▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✶✵✶✱ ♣❛❣❡s ✸✶✾✕✸✸✷✱ ✷✵✵✺✳ ✷

Page 150: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❇✐❜❧✐♦❣r❛♣❤② ✶✸✼

❬❉✐❡❝❦♠❛♥♥ ✶✾✾✾❪ ❯✳ ❉✐❡❝❦♠❛♥♥✳ ❋r♦♠ ■♥❞✐✈✐❞✉❛❧s t♦ P♦♣✉❧❛t✐♦♥s✿ ❙②st❡♠❛t✐❝

▼♦❞❡❧ ❘❡❞✉❝t✐♦♥ ✐♥ ❊✈♦❧✉t✐♦♥❛r② ❚❤❡♦r② ❛♥❞ ❙♣❛t✐❛❧ ❊❝♦❧♦❣②✳ ❘❛♣♣♦rt t❡❝❤✲

♥✐q✉❡✱ ❍❛❜✐❧✐t❛t✐♦♥ r❡♣♦rt ✲ ❲✐❡♥ ❯♥✐✈❡rs✐t②✱ ✶✾✾✾✳ ✸✶

❬❉✐❡❝❦♠❛♥♥ ✷✵✵✵❪ ❯✳ ❉✐❡❝❦♠❛♥♥✱ ❘✳ ▲❛✇ ❛♥❞ ❏✳❆✳❏ ▼❡t③✳ ❚❤❡ ❣❡♦♠❡tr② ♦❢ ❡❝♦✲

❧♦❣✐❝❛❧ ✐♥t❡r❛❝t✐♦♥s✿ s✐♠♣❧✐❢②✐♥❣ s♣❛t✐❛❧ ❝♦♠♣❧❡①✐t②✳ ❈❛♠❜r✐❞❣❡ ❯♥✐✈❡rs✐t②

Pr❡ss✱ ✷✵✵✵✳ ✷✱ ✻✱ ✷✾✱ ✸✼✱ ✹✷✱ ✹✸✱ ✻✶

❬❉♦❝❦❡r② ✷✵✵✶❪ ❏✳ ❉♦❝❦❡r② ❛♥❞ ■✳ ❑❧❛♣♣❡r✳ ❋✐♥❣❡r ❢♦r♠❛t✐♦♥ ✐♥ ❜✐♦✜❧♠ ❧❛②❡rs✳ ❙■❆▼

❏✳ ❆PP▲✳ ▼❛t❤✳✱ ✈♦❧✳ ✻✷✱ ♣❛❣❡s ✽✺✸✕✽✻✾✱ ✷✵✵✶✳ ✶✸

❬❊❜❡r❧ ✷✵✵✶❪ ❏✳ ❊❜❡r❧ ❍✳✱ ❉✳❋✳ P❛r❦❡r ❛♥❞ ▼✳❈✳▼✳ ❱❛♥ ▲♦♦s❞r❡❝❤t✳ ❆ ♥❡✇ ❞❡t❡r✲

♠✐♥✐st✐❝ s♣❛t✐♦✲t❡♠♣♦r❛❧ ❝♦♥t✐♥✉ ♠♦❞❡ ❢♦r ❜✐♦✜❧♠ ❞❡✈❡❧♦♣♠❡♥t✳ ❏♦✉r♥❛❧ ♦❢

❚❤❡♦r❡t✐❝❛❧ ▼❡❞✐❝✐♥❡✱ ✈♦❧✳ ✸✱ ♣❛❣❡s ✶✻✶✕✶✼✺✱ ✷✵✵✶✳ ✽✱ ✶✶✱ ✶✷✱ ✶✸✱ ✶✽✱ ✷✶✱ ✷✷

❬❊♠♦♥❡t ✷✵✵✺❪ ❚✳ ❊♠♦♥❡t✱ ❈✳▼✳ ◆♦rt❤✱ ❈✳❊✳ ❲✐❝❦❡rs❤❛♠ ❛♥❞ P✳ ❈❧✉③❡❧✳ ❆❣❡♥t❈❡❧❧✿

❛ ❞✐❣✐t❛❧ s✐♥❣❧❡✲❝❡❧❧ ❛ss❛② ❢♦r ❜❛❝t❡r✐❛❧ ❝❤❡♠♦t❛①✐s✳ ❇✐♦✐♥❢♦r♠❛t✐❝s✱ ✈♦❧✳ ✷✶✱

♣❛❣❡s ✷✼✶✹✕✷✼✱ ✷✵✵✺✳ ✷

❬❋❡rr❡r ✷✵✵✽❪ ❏✳ ❋❡rr❡r✱ ❈✳ Pr❛ts ❛♥❞ ❉✳ ▲♦♣❡③✳ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ▼♦❞❡❧❧✐♥❣✿ ❆♥

❊ss❡♥t✐❛❧ ❚♦♦❧ ❢♦r ▼✐❝r♦❜✐♦❧♦❣②✳ ❏ ❇✐♦❧ P❤②s✱ ✈♦❧✳ ✸✹✱ ♣❛❣❡s ✶✾✕✸✼✱ ✷✵✵✽✳ ✷✱

✻✾

❬●■❧❧❡s♣✐❡ ✶✾✼✻❪ ❚✳ ●■❧❧❡s♣✐❡ ❉✳ ❆ ❣❡♥❡r❛❧ ♠❡t❤♦❞ ❢♦r ♥✉♠❡r✐❝❛❧❧② s✐♠✉❧❛t✐♥❣ t❤❡

st♦❝❤❛st✐❝ t✐♠❡ ❡✈♦❧✉t✐♦♥ ♦❢ ❝♦✉♣❧❡❞ ❝❤❡♠✐❝❛❧ r❡❛❝t✐♦♥s✳ ❏♦✉r♥❛❧ ♦❢ ❈♦♠♣✉✲

t❛t✐♦♥❛❧ P❤②s✐❝s✱ ✈♦❧✳ ✷✷✱ ♣❛❣❡s ✹✵✸✕✹✸✹✱ ✶✾✼✻✳ ✸✶✱ ✽✾

❬●✐♥♦✈❛rt ✷✵✵✷❪ ▼❛rt❛ ●✐♥♦✈❛rt✱ ❉❛♥✐❡❧ ▲♦♣❡③ ❛♥❞ ❏♦❛q✉✐♠ ❱❛❧❧s✳ ■◆❉■❙■▼✱

❆♥ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ❉✐s❝r❡t❡ ❙✐♠✉❧❛t✐♦♥ ▼♦❞❡❧ t♦ ❙t✉❞② ❇❛❝t❡r✐❛❧ ❈✉❧t✉r❡s✳

❏♦✉r♥❛❧ ♦❢ ❚❤❡♦r❡t✐❝❛❧ ❇✐♦❧♦❣②✱ ✈♦❧✳ ✷✶✹✱ ♥♦✳ ✷✱ ♣❛❣❡s ✸✵✺✕✸✶✾✱ ❏❛♥✉❛r② ✷✵✵✷✳

✷✱ ✻✾

❬●r✐♠♠ ✶✾✾✾❪ ❱♦❧❦❡r ●r✐♠♠✱ ❚♦♠❛s③ ❲②s③♦♠✐rs❦✐✱ ❉❛✈✐❞ ❆✐❦♠❛♥ ❛♥❞ ❏❛♥✉s③ ❯❝❤✲

♠❛♥s❦✐✳ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧❧✐♥❣ ❛♥❞ ❡❝♦❧♦❣✐❝❛❧ t❤❡♦r②✿ s②♥t❤❡s✐s ♦❢ ❛ ✇♦r❦✲

s❤♦♣✳ ❊❝♦❧♦❣✐❝❛❧ ▼♦❞❡❧❧✐♥❣✱ ✈♦❧✳ ✶✶✺✱ ♥♦✳ ✷✲✸✱ ♣❛❣❡s ✷✼✺✕✷✽✷✱ ❋❡❜r✉❛r② ✶✾✾✾✳

✷✱ ✶✸✶

❬●r✐♠♠ ✷✵✵✺❪ ❱♦❧❦❡r ●r✐♠♠ ❛♥❞ ❙t❡✈❡♥ ❋✳ ❘❛✐❧s❜❛❝❦✳ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✐♥❣

❛♥❞ ❡❝♦❧♦❣②✳ Pr✐♥❝❡t♦♥ ❯♥✐✈❡rs✐t② Pr❡ss✱ ✷✵✵✺✳ ✹✱ ✺✱ ✽✹

❬●r✐♠♠ ✷✵✵✻❪ ❱♦❧❦❡r ●r✐♠♠✱ ❯t❛ ❇❡r❣❡r✱ ❋✐♥♥ ❇❛st✐❛♥s❡♥✱ ❙✐❣r✉♥♥ ❊❧✐❛ss❡♥✱ ❱✐♥✲

❝❡♥t ●✐♥♦t✱ ❏❛r❧ ●✐s❦❡✱ ❏♦❤♥ ●♦ss✲❈✉st❛r❞✱ ❚❛♠❛r❛ ●r❛♥❞✱ ❙✐♠♦♥❡ ❑✳ ❍❡✐♥③✱

●❡✐r ❍✉s❡✱ ❆♥❞r❡❛s ❍✉t❤✱ ❏❛♥❡ ❯✳ ❏❡♣s❡♥✱ ❈❤r✐st✐❛♥ ❏♦r❣❡♥s❡♥✱ ❲♦❧❢ ▼✳

▼♦♦✐❥✱ ❇✐r❣✐t ▼✉❧❧❡r✱ ●✉② P❡✬❡r✱ ❈②r✐❧ P✐♦✉✱ ❙t❡✈❡♥ ❋✳ ❘❛✐❧s❜❛❝❦✱ ❆♥❞r❡✇ ▼✳

❘♦❜❜✐♥s✱ ▼❛rt❤❛ ▼✳ ❘♦❜❜✐♥s✱ ❊✈❛ ❘♦ss♠❛♥✐t❤✱ ◆❛❞❥❛ ❘✉❣❡r✱ ❊s♣❡♥ ❙tr❛♥❞✱

❙❛♠✐ ❙♦✉✐ss✐✱ ❘✐❝❤❛r❞ ❆✳ ❙t✐❧❧♠❛♥✱ ❘✉♥❡ ❱❛❜♦✱ ❯t❡ ❱✐ss❡r ❛♥❞ ❉♦♥❛❧❞ ▲✳

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✶✸✽ ❇✐❜❧✐♦❣r❛♣❤②

❉❡❆♥❣❡❧✐s✳ ❆ st❛♥❞❛r❞ ♣r♦t♦❝♦❧ ❢♦r ❞❡s❝r✐❜✐♥❣ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ❛♥❞ ❛❣❡♥t✲

❜❛s❡❞ ♠♦❞❡❧s✳ ❊❝♦❧♦❣✐❝❛❧ ▼♦❞❡❧❧✐♥❣✱ ✈♦❧✳ ✶✾✽✱ ♥♦✳ ✶✲✷✱ ♣❛❣❡s ✶✶✺✕✶✷✻✱ ❙❡♣t❡♠✲

❜❡r ✷✵✵✻✳ ✸✱ ✺✱ ✼✱ ✽✱ ✶✷✱ ✻✾

❬●r✐♠s♦♥ ✶✾✾✹❪ ▼✳ ●r✐♠s♦♥ ❛♥❞ ●✳ ❇❛r❦❡r✳ ❈♦♥t✐♥✉✉♠ ♠♦❞❡❧ ❢♦r t❤❡ s♣❛t✐♦t❡♠♣♦r❛❧

❣r♦✇t❤ ♦❢ ❜❛❝t❡r✐❛❧ ❝♦❧♦♥✐❡s✳ P❤②s ❘❡✈ ❊✱ ✈♦❧✳ ✹✾✱ ♣❛❣❡s ✶✻✽✵✕✶✻✽✹✱ ✶✾✾✹✳ ✶✷

❬●✉❥❡r ✷✵✵✷❪ ❲✳ ●✉❥❡r✳ ▼✐❝r♦s❝♦♣✐❝ ✈❡rs✉s ♠❛❝r♦s❝♦♣✐❝ ❜✐♦♠❛ss ♠♦❞❡❧s ✐♥ ❛❝t✐✈❛t❡❞

s❧✉❞❣❡ s②st❡♠s✳ ❲❛t❡r ❙❝✐❡♥❝❡ ❛♥❞ ❚❡❝❤♥♦❧♦❣②✱ ✈♦❧✳ ✹✻✱ ♣❛❣❡s ✶✕✶✶✱ ✷✵✵✷✳ ✷

❬❍❡❧❧✇❡❣❡r ✷✵✵✾❪ ❋✳▲✳ ❍❡❧❧✇❡❣❡r ❛♥❞ ❱✳ ❇✉❝❝✐✳ ❆ ❜✉♥❝❤ ♦❢ t✐♥② ✐♥❞✐✈✐❞✉❛❧s ✲

■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧✐♥❣ ❢♦r ♠✐❝r♦❜❡s✳ ❊❝♦❧♦❣✐❝❛❧ ▼♦❞❡❧❧✐♥❣✱ ✈♦❧✳ ✷✷✵✱ ♣❛❣❡s

✽✕✷✷✱ ✷✵✵✾✳ ✷✱ ✹✱ ✻✾

❬❍❡r♥à♥❞❡③✲●❛r❝✐à ✷✵✵✹❪ ▲ó♣❡③ ❈✳ ❍❡r♥à♥❞❡③✲●❛r❝✐à ❊✳ ❈❧✉st❡r✐♥❣✱ ❛❞✈❡❝t✐♦♥ ❛♥❞

♣❛tt❡r♥s ✐♥ ❛ ♠♦❞❡ ♦❢ ♣♦♣✉❧❛t✐♦♥ ❞②♥❛♠✐❝s ✇✐t❤ ♥❡✐❣❤❜♦r❤♦♦❞✲❞❡♣❡♥❞❡♥t

r❛t❡s✳ P❤②s ❘❡✈ ❊✱ ✈♦❧✳ ✼✵✱ ✷✵✵✹✳ ✺✻

❬❏♦❤♥s♦♥ ✷✵✵✽❪ ▲❡❛❤ ❘✳ ❏♦❤♥s♦♥✳ ▼✐❝r♦❝♦❧♦♥② ❛♥❞ ❜✐♦✜❧♠ ❢♦r♠❛t✐♦♥ ❛s ❛ s✉r✈✐✈❛❧

str❛t❡❣② ❢♦r ❜❛❝t❡r✐❛✳ ❏♦✉r♥❛❧ ♦❢ ❚❤❡♦r❡t✐❝❛❧ ❇✐♦❧♦❣②✱ ✈♦❧✳ ✷✺✶✱ ♥♦✳ ✶✱ ♣❛❣❡s

✷✹✕✸✹✱ ▼❛r❝❤ ✷✵✵✽✳ ✽✹

❬❑❧❛✉s❡♥ ✵✵✸❛❪ ▼✳ ❑❧❛✉s❡♥✱ ❆✳ ❍❡②❞♦r♥✱ P✳ ❘❛❣❛s✱ ▲✳ ▲❛♠❜❡rts❡♥✱ ❆✳ ❆❛❡s✲

❏♦r❣❡♥s❡♥✱ ❙✳ ▼♦❧✐♥ ❛♥❞ ❚✳ ❚♦❧❦❡r✲◆✐❡❧s❡♥✳ ❇✐♦✜❧♠ ❢♦r♠❛t✐♦♥ ❜② Ps❡✉✲

❞♦♠♦♥❛s ❛❡r✉❣✐♥♦s❛ ✇✐❧❞ t②♣❡✱ ✢❛❣❡❧❧❛ ❛♥❞ t②♣❡ ■❱ ♣✐❧✐ ♠✉t❛♥ts✳ ▼♦❧❡❝✉❧❛r

▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✹✽✱ ♥♦✳ ✻✱ ♣❛❣❡s ✶✺✶✶✕✶✺✷✹✱ ❏✉♥❡ ✷✵✵✸❛✳ ✻✽✱ ✼✾

❬❑❧❛✉s❡♥ ✵✵✸❜❪ ▼✳ ❑❧❛✉s❡♥✱ ❆✳ ❆❛❡s✲❏♦r❣❡♥s❡♥✱ ❙✳ ▼♦❧✐♥ ❛♥❞ ❚✳ ❚♦❧❦❡r✲◆✐❡❧s❡♥✳

■♥✈♦❧✈❡♠❡♥t ♦❢ ❜❛❝t❡r✐❛❧ ♠✐❣r❛t✐♦♥ ✐♥ t❤❡ ❞❡✈❡❧♦♣♠❡♥t ♦❢ ❝♦♠♣❧❡① ♠✉❧t✐❝❡❧❧✉✲

❧❛r str✉❝t✉r❡s ✐♥ Ps❡✉❞♦♠♦♥❛s ❆❡r✉❣✐♥♦s❛ ❜✐♦✜❧♠s✳ ▼♦❧❡❝✉❧❛r ▼✐❝r♦❜✐♦❧♦❣②✱

✈♦❧✳ ✺✵✱ ♥♦✳ ✶✱ ♣❛❣❡s ✻✶✕✻✽✱ ❖❝t♦❜❡r ✷✵✵✸❜✳ ✻✽✱ ✼✼✱ ✼✾

❬❑♦❝❤ ✶✾✾✸❪ ▲✳ ❑♦❝❤ ❆✳ ❇✐♦♠❛ss ❣r♦✇t❤ r❛t❡ ❞✉r✐♥❣ t❤❡ ♣r♦❦❛r②♦t❡ ❝❡❧❧ ❝②❝❧❡✳ ❈r✐t

❘❡✈ ▼✐❝r♦❜✐♦❧✱ ✈♦❧✳ ✶✾✱ ♣❛❣❡s ✶✼✕✹✷✱ ✶✾✾✸✳ ✶✻

❬❑r❡❢t ✶✾✾✽❪ ❏✳❯✳ ❑r❡❢t✱ ●✳ ❇♦♦t❤ ❛♥❞ ❲✐♠♣❡♥♥② ❏✳❲✳❚✳ ❇❛❝s✐♠✱ ❛ s✐♠✉❧❛t♦r ❢♦r

✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧❧✐♥❣ ♦❢ ❜❛❝t❡r✐❛❧ ❝♦❧♦♥② ❣r♦✇t❤✳ ▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✶✹✹✱

♣❛❣❡s ✸✷✼✺✕✸✷✼✽✱ ✶✾✾✽✳ ✶✱ ✽✱ ✶✶✱ ✶✸✱ ✶✻

❬❑r❡❢t ✶✾✾✾❪ ❏ ❯ ❑r❡❢t✱ ● ❇♦♦t❤ ❛♥❞ ❏ ❲ ❚ ❲✐♠♣❡♥♥②✳ ❆♣♣❧✐❝❛t✐♦♥s ♦❢ ✐♥❞✐✈✐❞✉❛❧✲

❜❛s❡❞ ♠♦❞❡❧❧✐♥❣ ✐♥ ♠✐❝r♦❜✐❛❧ ❡❝♦❧♦❣②✳ ■♥ ❏♦❤♥s♦♥ ●r❡❡♥ ❇❡❧❧ ❈ ❘ ❇r②❧✐♥✲

s❦② ▼✱ ❡❞✐t❡✉r✱ ▼✐❝r♦❜✐❛❧ ❇✐♦s②st❡♠s✿ ◆❡✇ ❋r♦♥t✐❡rs✳ Pr♦❝❡❡❞✐♥❣ ♦❢ t❤❡ ✽t❤

■♥t❡r♥❛t✐♦♥❛❧ ❙②♠♣♦s✐✉♠ ♦♥ ▼✐❝r♦❜✐❛❧ ❊❝♦❧♦❣②✱ ✶✾✾✾✳ ✷

❬❑r❡❢t ✷✵✵✶❪ ❏❛♥✲❯❧r✐❝❤ ❑r❡❢t✱ ❈r✐st✐❛♥ P✐❝✐♦r❡❛♥✉✱ ❏✉❧✐❛♥ ❲✳❚✳ ❲✐♠♣❡♥♥② ❛♥❞

▼❛r❝❦ ❈✳▼✳ ✈❛♥ ▲♦♦s❞r❡❝❤t✳ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧❧✐♥❣ ♦❢ ❜✐♦✜❧♠s✳ ▼✐✲

❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✶✹✼✱ ♣❛❣❡s ✷✽✾✼✕✷✾✶✷✱ ✷✵✵✶✳ ✷✱ ✸✱ ✶✶✱ ✶✷✱ ✶✻✱ ✻✾✱ ✼✶✱ ✼✺

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❇✐❜❧✐♦❣r❛♣❤② ✶✸✾

❬▲❛❝❛st❛ ✶✾✾✾❪ ❆✳▼✳ ▲❛❝❛st❛✱ ■✳❘✳ ❈❛♥t❛❧❛♣✐❡❞r❛✱ ❈✳❊✳ ❆✉❣✉❡t✱ ❆✳ P❡❛r❛♥❞❛ ❛♥❞

▲✳ ❘❛♠✐r❡③✲P✐s❝✐♥❛✳ ▼♦❞❡❧❧✐♥❣ ♦❢ s♣❛t✐♦✲t❡♠♣♦r❛❧ ♣❛tt❡r♥s ✐♥ ❜❛❝t❡r✐❛❧

❝♦❧♦♥✐❡s✳ P❤②s✳ ❘❡✈✳ ❊✱ ✈♦❧✳ ✺✾✱ ♣❛❣❡s ✼✵✸✻ ✕ ✼✵✹✶✱ ✶✾✾✾✳ ✶✷

❬▲❛s♣✐❞♦✉ ✷✵✵✾❪ ❈✳❙✳ ▲❛s♣✐❞♦✉✱ ❆✳ ❑✉♥❣♦❧♦s ❛♥❞ P✳ ❙❛♠❛r❛s✳ ❈❡❧❧✉❧❛r✲❛✉t♦♠❛t❛

❛♥❞ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ❛♣♣r♦❛❝❤❡s ❢♦r t❤❡ ♠♦❞❡❧ ♦❢ ❜✐♦✜❧♠ str✉❝t✉r❡✿ Pr♦s ❛♥❞

❝♦♥s✳ ❉❡s❛❧✐♥❛t✐♦♥✱ ✈♦❧✳ ❆rt✐❝❧❡ ✐♥ Pr❡ss✱ ✷✵✵✾✳ ✸

❬▲❛✇ ✷✵✵✵❪ ❘✳ ▲❛✇ ❛♥❞ ❯✳ ❉✐❡❝❦♠❛♥♥✳ ▼♦♠❡♥t ❛♣♣r♦①✐♠❛t✐♦♥s ♦❢ ✐♥❞✐✈✐❞✉❛❧✲❜❛s❡❞

♠♦❞❡❧s✱ ❝❤❛♣✐tr❡ ✶✹✱ ♣❛❣❡s ✷✺✷✕✷✼✵✳ ❈❛♠❜r✐❞❣❡ ❯♥✐✈❡rs✐t② Pr❡ss✱ ✷✵✵✵✳ ✸✽

❬▲❡❡ ✷✵✵✶❪ ❈✳ ▲❡❡✱ ▼✳ ❍♦♦♣❡s✱ ❏✳ ❉✐❡❤❧✱ ❲✳ ●✐❧❧✐❧❛♥❞✱ ●✳ ❍✉①❡❧✱ ❊✳ ▲❡❛✈❡r✱ ❑✳ ▼❝✲

❈❛♥♥✱ ❏✳ ❯♠❜❛♥❤♦✇❛r ❛♥❞ ❆✳ ▼♦❣✐❧♥❡r✳ ◆♦♥✲❧♦❝❛❧ ❝♦♥❝❡♣ts ❛♥❞ ♠♦❞❡❧s ✐♥

❜✐♦❧♦❣②✳ ❏♦✉r♥❛❧ ♦❢ ❚❤❡♦r❡t✐❝❛❧ ❇✐♦❧♦❣②✱ ✈♦❧✳ ✷✶✵✱ ♣❛❣❡s ✷✵✶✕✷✶✾✱ ✷✵✵✶✳ ✽✹

❬▲❡✈✐♥ ✶✾✾✽❪ ❙✳ ❆✳ ▲❡✈✐♥✳ ❊❝♦s②st❡♠s ❛♥❞ t❤❡ ❜✐♦s♣❤❡r❡ ❛s ❝♦♠♣❧❡① ❛❞❛♣t❛t✐✈❡ s②s✲

t❡♠s✳ ❊❝♦s②st❡♠s✱ ✈♦❧✳ ✶✱ ♣❛❣❡s ✹✸✶✕✹✸✻✱ ✶✾✾✽✳ ✶

❬▲♦❜r② ✷✵✵✸❪ ❈✳ ▲♦❜r②✳ ▼♦❞è❧❡s ♠❛t❤é♠❛t✐q✉❡s ❡t ♠♦❞è❧❡s ✐♥❢♦r♠❛t✐q✉❡s✱ s✉r ❧❛

t❤é♦r✐❡ ❞✉ ♠♦❞è❧❡✳ ❆♥♥❛❧❡s ❞❡s P♦♥ts ❡t ❈❤❛✉ssé❡s✱ ✈♦❧✳ ✶✵✼✲✶✵✽✱ ♣❛❣❡s ✶✵✕

✶✽✱ ✷✵✵✸✳ ✶

❬▲✉ ✷✵✵✺❪ ❆♥♥ ▲✉✱ ❑②✉♥②✉♥❣ ❈❤♦✱ ❲❡s❧❡② P✳ ❇❧❛❝❦✱ ❳✉❡✲②❛♥ ❉✉❛♥✱ ❘❡♥❛t❡ ▲✉①✱

❩❤❛♦♠✐♥ ❨❛♥❣✱ ❍❡✐❞✐ ❇✳ ❑❛♣❧❛♥✱ ❉❛✈✐❞ ❘✳ ❩✉s♠❛♥ ❛♥❞ ❲❡♥②✉❛♥ ❙❤✐✳ ❊①✲

♦♣♦❧②s❛❝❝❤❛r✐❞❡ ❜✐♦s②♥t❤❡s✐s ❣❡♥❡s r❡q✉✐r❡❞ ❢♦r s♦❝✐❛❧ ♠♦t✐❧✐t② ✐♥ ▼②①♦❝♦❝❝✉s

①❛♥t❤✉s✳ ▼♦❧❡❝✉❧❛r ▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✺✺✱ ♥♦✳ ✶✱ ♣❛❣❡s ✷✵✻✕✷✷✵✱ ✷✵✵✺✳ ✽✹

❬▲✉❦❡ ✷✵✵✹❪ ❙✳ ▲✉❦❡✱ ❈✳ ❈✐♦✣✲❘❡✈✐❧❧❛✱ ▲✳ P❛♥❛✐t ❛♥❞ ❑✳ ❙✉❧❧✐✈❛♥✳ ▼❆❙❖◆ ✿ ❆

❏❛✈❛ ▼✉❧t✐✲❆❣❡♥t ❙✐♠✉❧❛t✐♦♥ ❚♦♦❧❦✐t✳ Pr♦❝❡❡❞✐♥❣s ♦❢ t❤❡ ✷✵✵✹ ❙✇❛r♠❋❡st

❲♦r❦s❤♦♣✱ ✷✵✵✹✳ ✽✱ ✼✻

❬▼❝❑❛♥❡ ✷✵✵✹❪ ❆✳ ❏✳ ▼❝❑❛♥❡ ❛♥❞ ❚✳ ❏✳ ◆❡✇♠❛♥✳ ❙t♦❝❤❛st✐❝ ♠♦❞❡❧s ✐♥ ♣♦♣✉❧❛t✐♦♥

❜✐♦❧♦❣② ❛♥❞ t❤❡✐r ❞❡t❡r♠✐♥✐st✐❝ ❂ ❛♥❛❧♦❣s✱ ❖❝t♦❜❡r ✷✵✵✹✳ ✹

❬▼♦r❣❡♥r♦t❤ ✶✾✾✼❪ ❊✳ ▼♦r❣❡♥r♦t❤✱ ❚✳ ❙❤❡r❞❡♥❛✱ ▼✳ ❈✳ ▼✳ ❱❛♥ ▲♦♦s❞r❡❝❤t ▼✳❈✳▼✳✱

❏✳❏✳ ❍❡✐❥♥❡♥ ❛♥❞ P✳❆✳ ❲✐❧❞❡r❡r✳ ❆❡r♦❜✐❝ ❣r❛♥✉❧❛r s❧✉❞❣❡ ✐♥ ❛ s❡q✉❡♥❝✐♥❣

❜❛t❝❤ r❡❛❝t♦r✳ ❲❛t❡r ❘❡s❡❛r❝❤✱ ✈♦❧✳ ✸✶✱ ♣❛❣❡s ✸✶✾✶✕✸✶✾✹✱ ✶✾✾✼✳ ✶✷

❬▼♦r❣❡♥r♦t❤ ✷✵✵✵❪ ❊✳ ▼♦r❣❡♥r♦t❤ ❛♥❞ P✳❆✳ ❲✐❧❞❡r❡r✳ ■♥✢✉❡♥❝❡ ♦❢ ❞❡t❛❝❤♠❡♥t

♠❡❝❤❛♥✐s♠s ♦♥ ❝♦♠♣❡t✐t✐♦♥ ✐♥ ❜✐♦✜❧♠s✳ ❲❛t❡r ❘❡s❡❛r❝❤✱ ✈♦❧✳ ✸✹✱ ♣❛❣❡s ✹✶✼✕

✹✷✻✱ ✷✵✵✵✳ ✺✹

❬▼✉r♣❤② ✷✵✵✽❪ ❚✳ ▼✉r♣❤② ❏✳✱ ❘✳ ❲❛❧s❤❡ ❛♥❞ ▼✳ ❉❡✈♦❝❡❧❧❡✳ ❆♥ ❆❣❡♥t ❇❛s❡❞ ❆♣✲

♣r♦❛❝❤ t♦ ▼♦❞❡❧❧✐♥❣ ▼✐❝r♦❜✐❛❧ ❊❝♦s②st❡♠s✳ ❊❘❈■▼ ◆❡✇s✱ ✈♦❧✳ ✭❛♣r✐❧✮✱ ✷✵✵✽✳

❬▼✉rr❛② ✷✵✵✶❪ ❏✳❉✳ ▼✉rr❛②✳ ▼❛t❤❡♠❛t✐❝❛❧ ❜✐♦❧♦❣②✿ ■✳ ❛♥ ✐♥tr♦❞✉❝t✐♦♥✳ ❙♣r✐♥❣❡r✱

✸r❞ ❡❞✳ ✷✵✵✶✳ ✶✶

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✶✹✵ ❇✐❜❧✐♦❣r❛♣❤②

❬▼✉rr❡❧❧ ✷✵✵✵❪ ❉✳❏✳ ▼✉rr❡❧❧ ❛♥❞ ❘✳ ▲❛✇✳ ❇❡❡t❧❡s ✐♥ ❢r❛❣♠❡♥t❡❞ ✇♦♦❞❧❛♥❞s✿ ❛ ❢♦r♠❛❧

❢r❛♠❡✇♦r❦ ❢♦r ❞②♥❛♠✐❝s ♦❢ ♠♦✈❡♠❡♥t ✐♥ ❡❝♦❧♦❣✐❝❛❧ ❧❛♥❞s❝❛♣❡s✳ ❏♦✉r♥❛❧ ♦❢

❆♥✐♠❛❧ ❊❝♦❧♦❣②✱ ✈♦❧✳ ✻✾✱ ♥♦✳ ✸✱ ♣❛❣❡s ✹✼✶✕✹✽✸✱ ✷✵✵✵✳ ✺✱ ✻✱ ✶✷✾

❬❖✬❚♦♦❧❡ ✷✵✵✵❪ ●✳ ❖✬❚♦♦❧❡✱ ❍✳ ❑❛♣❧❛♥ ❛♥❞ ❘✳ ❑♦❧t❡r✳ ❇✐♦✜❧♠ ❢♦r♠❛t✐♦♥ ❛s ♠✐❝r♦❜✐❛❧

❞❡✈❡❧♦♣♠❡♥t✳ ❆♥♥✉ ❘❡✈ ▼✐❝r♦❜✐♦❧✱ ✈♦❧✳ ✺✹✱ ♣❛❣❡s ✹✾✕✼✾✱ ✷✵✵✵✳ ✷

❬P❛rs❡❦ ✷✵✵✽❪ ▼❛tt❤❡✇ ❘ P❛rs❡❦ ❛♥❞ ❚✐♠ ❚♦❧❦❡r✲◆✐❡❧s❡♥✳ P❛tt❡r♥ ❢♦r♠❛t✐♦♥ ✐♥

Ps❡✉❞♦♠♦♥❛s ❛❡r✉❣✐♥♦s❛ ❜✐♦✜❧♠s✳ ❈✉rr❡♥t ❖♣✐♥✐♦♥ ✐♥ ▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✶✶✱

♥♦✳ ✻✱ ♣❛❣❡s ✺✻✵✕✺✻✻✱ ❉❡❝❡♠❜❡r ✷✵✵✽✳ ✻✽✱ ✽✹

❬P✐❝✐♦r❡❛♥✉ ✷✵✵✹❪ ❈r✐st✐❛♥ P✐❝✐♦r❡❛♥✉✱ ❏❛♥✲❯❧r✐❝❤ ❑r❡❢t ❛♥❞ ▼❛r❦ ❈✳ ▼✳ ✈❛♥ ▲♦♦s✲

❞r❡❝❤t✳ P❛rt✐❝❧❡✲❇❛s❡❞ ▼✉❧t✐❞✐♠❡♥s✐♦♥❛❧ ▼✉❧t✐s♣❡❝✐❡s ❇✐♦✜❧♠ ▼♦❞❡❧✳ ❆♣♣❧✳

❊♥✈✐r♦♥✳ ▼✐❝r♦❜✐♦❧✳✱ ✈♦❧✳ ✼✵✱ ♥♦✳ ✺✱ ♣❛❣❡s ✸✵✷✹✕✸✵✹✵✱ ✷✵✵✹✳ ✷✱ ✸✱ ✶✶✱ ✶✷

❬P✐❝✐♦r❡❛♥✉ ✷✵✵✺❪ ❈✳ P✐❝✐♦r❡❛♥✉✱ ❉✳❏✳ ❇❛tst♦♥❡ ❛♥❞ ▼✳❈✳▼✳ ❱❛♥ ▲♦♦s❞r❡❝❤t✳ ▼✉❧t✐✲

❞✐♠❡♥s✐♦♥❛❧ ♠♦❞❡❧❧✐♥❣ ♦❢ ❛♥❛❡r♦❜✐❝ ❣r❛♥✉❧❡s✳ ❲❛t❡r ❙❝✐❡♥❝❡ ❛♥❞ ❚❡❝❤♥♦❧♦❣②✱

✈♦❧✳ ✺✸✱ ♣❛❣❡s ✺✵✶✕✺✵✼✱ ✷✵✵✺✳ ✷

❬P✐❝✐♦r❡❛♥✉ ✷✵✵✼❪ ❈✳ P✐❝✐♦r❡❛♥✉✱ ❏✲❯ ❑r❡❢t✱ ▼✳ ❑❧❛✉ss❡♥✱ ❏✳❆✳❏✳ ❍❛❛❣❡♥s❡♥✱

❚✳ ❚♦❧❦❡r✲◆✐❡❧s❡♥ ❛♥❞ ❙✳ ▼♦❧✐♥✳ ▼✐❝r♦❜✐❛❧ ♠♦❜✐❧✐t② ✐♥✈♦❧✈❡♠❡♥t ✐♥ ❜✐♦✜❧♠

str✉❝t✉r❡ ❢♦r♠❛t✐♦♥ ✲ ❛ ✸❉ ♠♦❞❡❧❧✐♥❣ st✉❞②✳ ❲❛t❡r ❙❝✐❡♥❝❡ ✫ ❚❡❝❤♥♦❧♦❣②✱

✈♦❧✳ ✺✺✱ ♣❛❣❡s ✸✸✼✕✸✹✸✱ ✷✵✵✼✳ ✻✾✱ ✼✻✱ ✼✼✱ ✼✾

❬❘❛✐❧s❜❛❝❦ ✷✵✵✶❪ ❋✳ ❘❛✐❧s❜❛❝❦ ❙t❡✈❡♥✳ ❈♦♥❝❡♣ts ❢r♦♠ ❈♦♠♣❧❡① ❆❞❛♣t❛t✐✈❡ ❙②s✲

t❡♠s ❛s ❛ ❋r❛♠❡✇♦r❦ ❢♦r ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ▼♦❞❡❧❧✐♥❣✳ ❊❝♦❧♦❣✐❝❛❧ ▼♦❞❡❧❧✐♥❣✱

✈♦❧✳ ✶✸✾✱ ♣❛❣❡s ✹✼✕✻✷✱ ✷✵✵✶✳ ✶

❬❘❛♠♠❡❧ ✷✵✵✼❪ ❈✳ ❘❛♠♠❡❧✱ ❙✳ ❙t❛❣❧ ❛♥❞ ❍✳ ❲✐❧✜♥❣✳ ▼❛♥❛❣✐♥❣ ❈♦♠♣❧❡① ❆❞❛♣t✐✈❡

s②st❡♠s✿ ❆ ❈♦✲❊✈♦❧✉t✐♦♥❛r② P❡rs♣❡❝t✐✈❡ ♦♥ ◆❛t✉r❛❧ ❘❡s♦✉r❝❡ ▼❛♥❛❣❡♠❡♥t✳

❊❝♦❧♦❣✐❝❛❧ ❊❝♦♥♦♠✐❝s✱ ✈♦❧✳ ✻✸✱ ♣❛❣❡s ✾✕✷✶✱ ✷✵✵✼✳ ✶

❬❙❝❤♠✐❞ ✷✵✵✸❪ ▼✳ ❙❝❤♠✐❞✱ ❆✳ ❚❤✐❧❧✱ ❯✳ P✉r❦❤♦❧❞✱ ▼✳ ❲❛❧❝❤❡r✱ ❏✳✲❨✳ ❇♦tt❡r♦✱

P✳ ●✐♥❡st❡t✱ P✳❍✳ P❡r ❍❛❧❦❥❛❡r ◆✐❡❧s❡♥✱ ❙✳ ❲✉❡rt③ ❛♥❞ ▼✳ ❲❛❣♥❡r✳ ❈❤❛r❛❝✲

t❡r✐③❛t✐♦♥ ♦❢ ❛❝t✐✈❛t❡❞ s❧✉❞❣❡ ✢♦❝s ❜② ❝♦♥❢♦❝❛❧ ❧❛s❡r s❝❛♥♥✐♥❣ ♠✐❝r♦s❝♦♣② ❛♥❞

✐♠❛❣❡ ❛♥❛❧②s✐s✳ ❲❛t❡r ❘❡s❡❛r❝❤✱ ✈♦❧✳ ✸✼✱ ♣❛❣❡s ✷✵✹✸✕✷✵✺✷✱ ✷✵✵✸✳ ✶✷

❬❙t❡✇❛rt ✶✾✾✸❪ P✳ ❙✳ ❙t❡✇❛rt✳ ❆ ▼♦❞❡❧ ❢♦r ❇✐♦✜❧♠ ❉❡t❛❝❤♠❡♥t✳ ❇✐♦t❡❝❤ ❇✐♦❡♥❣✱

✈♦❧✳ ✹✶✱ ♣❛❣❡s ✶✶✶✕✶✶✼✱ ✶✾✾✸✳ ✺✹

❬❚♦❧❦❡r✲◆✐❡❧s❡♥ ✷✵✵✵❪ ❚✐♠ ❚♦❧❦❡r✲◆✐❡❧s❡♥✱ ❯✳ ❈✳ ❇r✐♥❝❤✱ P✳ ❈✳ ❘❛❣❛s✱ ❏✳ ❇✳ ❆♥❞❡r✲

s❡♥✱ ❈❛rst❡♥ ❙✉❤r ❏✳ ❛♥❞ ❙✳ ▼♦❧✐♥✳ ❉❡✈❡❧♦♣♠❡♥t ❛♥❞ ❉②♥❛♠✐❝s ♦❢ Ps❡✉✲

❞♦♠♦♥❛s s♣✳ ❇✐♦✜❧♠s✳ ❏✳ ❇❛❝t❡r✐♦❧✳✱ ✈♦❧✳ ✶✽✷✱ ♥♦✳ ✷✷✱ ♣❛❣❡s ✻✹✽✷✕✻✹✽✾✱

◆♦✈❡♠❜❡r ✷✵✵✵✳ ✺✹

❬❚r❡✉✐❧ ✷✵✵✽❪ ❏✳P✳ ❚r❡✉✐❧✱ ❉✳ ❩✉❝❦❡r ❛♥❞ ❆✳ ❉r♦❣♦✉❧✳ ▼♦❞é❧✐s❛t✐♦♥ ❡t s✐♠✉❧❛t✐♦♥ à

❜❛s❡ ❞✬❛❣❡♥ts✳ ✷✵✵✽✳ ✸

Page 154: Analyzing individual-based models of microbial systems · HAL Id: tel-00712153  Submitted on 26 Jun 2012 HAL is a multi-disciplinary open access archive for the deposit and

❇✐❜❧✐♦❣r❛♣❤② ✶✹✶

❬❯❝❤♠❛♥s❦✐ ✶✾✾✻❪ ❏❛♥✉s③ ❯❝❤♠❛♥s❦✐ ❛♥❞ ❱♦❧❦❡r ●r✐♠♠✳ ■♥❞✐✈✐❞✉❛❧✲❜❛s❡❞ ♠♦❞❡❧❧✐♥❣

✐♥ ❡❝♦❧♦❣②✿ ✇❤❛t ♠❛❦❡s t❤❡ ❞✐✛❡r❡♥❝❡❄ ❚r❡♥❞s ✐♥ ❊❝♦❧♦❣② ✫ ❊✈♦❧✉t✐♦♥✱

✈♦❧✳ ✶✶✱ ♥♦✳ ✶✵✱ ♣❛❣❡s ✹✸✼✕✹✹✶✱ ❖❝t♦❜❡r ✶✾✾✻✳ ✸✱ ✶✸✶

❬❱❛♥ ❇❛❛❧❡♥ ✷✵✵✵❪ ▼✳ ❱❛♥ ❇❛❛❧❡♥✳ ❚❤❡ ❣❡♦♠❡tr② ♦❢ ❡❝♦❧♦❣✐❝❛❧ ✐♥t❡r❛❝t✐♦♥s✿ ❙✐♠♣❧✐✲

❢②✐♥❣ s♣❛t✐❛❧ ❝♦♠♣❧❡①✐t②✒ ❝❤❛♣✐tr❡ P❛✐r ❛♣♣r♦①✐♠❛t✐♦♥s ❢♦r ❞✐✛❡r❡♥t s♣❛t✐❛❧

❣❡♦♠❡tr✐❡s✱ ♣❛❣❡s ✸✺✾✕✸✽✼✳ ❈❛♠❜r✐❞❣❡ ❯♥✐✈❡rs✐t② Pr❡ss✱ ✷✵✵✵✳ ✼

❬❱❛♥ ❙❝❤❛✐❦ ✷✵✵✺❪ ❊✳❏✳ ❱❛♥ ❙❝❤❛✐❦✱ ❈✳▲✳ ●✐❧t♥❡r✱ ●✳❋✳ ❆✉❞❡tt❡✱ ❉✳❲✳ ❑❡✐③❡r✱ ❉✳▲✳

❇❛✉t✐st❛✱ ❈✳▼✳ ❙❧✉♣s❦②✱ ❇✳❉✳ ❙②❦❡s ❛♥❞ ❘✳❚✳ ■r✈✐♥✳ ❉◆❆ ❇✐♥❞✐♥❣✿ ❛ ◆♦✈❡❧

❋✉♥❝t✐♦♥ ♦❢ Ps❡✉❞♦♠♦♥❛s ❛❡r✉❣✐♥♦s❛ ❚②♣❡ ■❱ P✐❧✐✳ ❏♦✉r♥❛❧ ♦❢ ❇❛❝t❡r✐♦❧♦❣②✱

✈♦❧✳ ✶✽✼✱ ♥♦✳ ✹✱ ♣❛❣❡s ✶✹✺✺✕✶✹✻✹✱ ❋❡❜r✉❛r② ✷✵✵✺✳ ✻✽

❬❱❧❛❝❤♦s ✷✵✵✻❪ ❈✳ ❱❧❛❝❤♦s✱ ❘✳❈✳ P❛t♦♥✱ ❏✳❘✳ ❙❛✉♥❞❡rs ❛♥❞ ◗✳❍✳ ❲✉✳ ❆ r✉❧❡✲❜❛s❡❞

❛♣♣r♦❛❝❤ t♦ t❤❡ ♠♦❞❡❧❧✐♥❣ ♦❢ ❜❛❝t❡r✐❛❧ ❡❝♦s②st❡♠s✳ ❇✐♦s②st❡♠s✱ ✈♦❧✳ ✽✹✱ ♣❛❣❡s

✹✾✕✼✷✱ ✷✵✵✻✳ ✸

❬❲❤✐t❝❤✉r❝❤ ✷✵✵✷❪ ❈✳❇✳ ❲❤✐t❝❤✉r❝❤✱ ❚✳ ❚♦❧❦❡r✲◆✐❡❧s❡♥✱ P❛✉❧❛ ❈✳ ❘❛❣❛s ❛♥❞ ❏♦❤♥ ❙✳

▼❛tt✐❝❦✳ ❊①tr❛❝❡❧❧✉❧❛r ❉◆❆ r❡q✉✐r❡❞ ❢♦r ❜❛❝t❡r✐❛❧ ❜✐♦✜❧♠ ❢♦r♠❛t✐♦♥✳ ❙❝✐❡♥❝❡✱

✈♦❧✳ ✷✾✺✱ ♣❛❣❡s ✶✹✽✼✕✶✹✽✼✱ ✷✵✵✷✳ ✻✽✱ ✼✾

❬❳❛✈✐❡r ✷✵✵✺❪ ❏♦❛♦ ❇✳ ❳❛✈✐❡r✱ ❈r✐st✐❛♥ P✐❝✐♦r❡❛♥✉ ❛♥❞ ▼❛r❦ ❈✳ ▼✳ ✈❛♥ ▲♦♦s❞r❡❝❤t✳

❆ ❢r❛♠❡✇♦r❦ ❢♦r ♠✉❧t✐❞✐♠❡♥s✐♦♥❛❧ ♠♦❞❡❧❧✐♥❣ ♦❢ ❛❝t✐✈✐t② ❛♥❞ str✉❝t✉r❡ ♦❢ ♠✉❧✲

t✐s♣❡❝✐❡s ❜✐♦✜❧♠s✳ ❊♥✈✐r♦♥♠❡♥t❛❧ ▼✐❝r♦❜✐♦❧♦❣②✱ ✈♦❧✳ ✼✱ ♣❛❣❡s ✶✵✽✺✕✶✶✵✸✱

✷✵✵✺✳ ✷✱ ✶✶✱ ✻✾

❬❳❛✈✐❡r ✷✵✵✾❪ ❏✳❇✳ ❳❛✈✐❡r✱ ❊✳ ▼❛rt✐♥❡③✲●❛r❝✐❛ ❛♥❞ ❑✳❘✳ ❋♦st❡r✳ ❙♦❝✐❛❧ ❊✈♦❧✉t✐♦♥

♦❢ ❙♣❛t✐❛❧ P❛tt❡r♥s ✐♥ ❇❛❝t❡r✐❛❧ ❇✐♦✜❧♠s✿ ✇❤❡♥ ❝♦♥✢✐❝t ❞r✐✈❡s ❞✐s♦r❞❡r✳ ❚❤❡

❆♠❡r✐❝❛♥ ◆❛t✉r❛❧✐st✱ ✈♦❧✳ ✶✼✹✱ ♣❛❣❡s ✶✕✶✷✱ ✷✵✵✾✳ ✶✶✾✱ ✶✷✵